Spring 2016 Report

Flower01

It is deja vu! Spring 2016 was wet like Spring 2015 despite El Nino fading. To make matters worse, there was severe flooding in April and May, which dumped up to 24 inches of rain in both events! That is something you see with tropical cyclones or core rain events with warm core low pressure systems. They are often from tropical cyclones.

For Texas, it has been mostly wet. For others, where’s the rain?

2016_SpringPrecipitationDivisionalRanks

2016_SpringTemperatureDivisionalRanks

America 2016 Spring
Mean Temperature: 53.68°F
Total Rainfall: 9.03

America Spring Temperature (1895-2016)
Mean: 51.10°F
Median: 50.87°F
Standard Deviation: 1.39
Lowest: 56.18°F (2012)
Highest: 47.37°F (1917)

America Spring Rainfall (1895-2016)
Mean: 7.95
Median: 7.95
Standard Deviation: 0.98
Lowest: 5.58 (1925)
Highest: 10.40 (1991)

It was a warm spring, but not a record breaking spring for America. It is nowhere like 2012. The average temperature is 1 standard deviation from the mean in terms of temperature. That is unusual, but not extraordinarily warm. If it was 2 standard deviation or greater that would be abnormal. It was abnormally warm for spring time in America.

It was much wetter as a whole. In fact, the Spring 2016 rainfall total is exceeds by 1 standard deviation. It was a wet spring for most of America.

Texas 2016 Spring
Mean Temperature: 66.27°F
Total Rainfall: 11.90

Texas Spring Temperature (1895-2016)
Mean: 64.76°F
Median: 64.73°F
Standard Deviation: 1.76
Lowest: 69.67°F (2012)
Highest: 59.93°F (1931)

Texas Spring Rainfall (1895-2016)
Mean: 7.37
Median: 7.05
Standard Deviation: 2.34
Lowest: 2.53 (2011)
Highest: 16.48 (2015)

It was warmer than normal for spring in Texas. It is 1 standard deviation from the mean.

It is wet, but not like 2015, which was wetter. Actually, it is the eighth wettest spring on record as it ties with 1914. It was indeed a wet spring for Texas, like last spring. Having two wet springs back to back is a rarity. Here is the top 10 wettest spring in Texas since 1895.

Top 10 Wettest Spring In Texas
1.) 2015 16.48
2.) 1957 14.75
3.) 1905 12.59
4.) 1941 12.43
5.) 1900 12.36
6.) 2007 12.16
7,) 1922 11.97
8.) 1914/2016 11.90
9.) 1997 10.85
10.) 1929 10.79

Many of the wettest springs occurred when El Nino is developing (1914, 1957, 1997, and 2015), persistent (1905 and 1941) or dying (1900 and 2007). 1922 was La Nina, while 1929 was Neutral. It shows that El Nino does have an impact on spring rainfall,whether is strengthening or dying. Interesting to note hurricanes made hurricanes made landfall in 1900, 1929, 1941, 1957, and 2007. Two were major hurricanes, Galveston Hurricane and Audrey in 1957.

Upper Texas Coast 2016 Spring
Mean Temperature: 71.07°F
Total Rainfall: 20.77

Upper Texas Coast Spring Temperature (1895-2016)
Mean: 68.54°F
Median: 68.42°F
Standard Deviation: 1.69
Lowest: 72.83°F (2012)
Highest: 63.37°F (1931)

Upper Texas Coast Spring Rainfall (1895-2016)
Mean: 10.58
Median: 10.02
Standard Deviation: 4.53
Lowest: 2.43 (2011)
Highest: 24.75 (2015)

It has been a warm spring. It is nearly 2 standard deviations from the mean. It was abnormally warm spring. It is the eighth warmest spring for Upper Texas Coast. Here is the top 10 warmest spring in Texas since 1895.

Top 10 Warmest Spring In Upper Texas Coast
1.) 2012 72.83°F
2.) 2011 72.03°F
3.) 2006 72.00°F
4.) 2000 71.57°F
5.) 1967 71.43°F
6.) 1963 71.40°F
7.) 1908 71.37°F
8.) 2016 71.07°F
9.) 1991 71.00°F
10.) 1925 70.97°F

Spring 2012 was warm everywhere, especially up north. 2011 was very warm as well. Who could forget Summer 2011? It was Hell for sure, which was made worse by the drought. The warmth is due to abnormally warm low temperatures. All that heavy rain makes the air more humid. Humidity keepers temperatures from going too cold or hot. It is the seventh warmest low temperature for spring. Here is a divisional ranking map of low and high temperatures.

2016_SpringMinTemperatureDivisionalRanks

2016_SpringMaxTemperatureDivisionalRanks

It was very west for Upper Texas Coast. It exceeds 2 standard deviations, which makes a near outlier. In fact, it is the third wettest spring on record! Yes, third wettest. There have been two back to back wet springs in the Upper Texas Coast. Here is the top 10 wettest spring in Upper Texas Coast since 1895.

Top 10 Wettest Spring In Upper Texas Coast
1.) 2015 24.75
2.) 1997 22.18
3.) 2016 20.77
4.) 1900 19.54
5.) 1957 19.32
6.) 1929 19.06
7.) 1914 18.54
8.) 1944 18.33
9.) 1993 18.32
10.) 1905 17.60

Many of the wettest springs for Upper Texas Coast occurred when El Nino is developing (1914, 1957, 1997, and 2015), persistent (1905) or dying (1900). 1944 had a developing La Nina from Neutral. 1929 was Neutral. April and May 1929 had heavy rain that led to massive flooding in the Houston area. The 1929 flood is considered an epic flood on par with December 1935 and Tropical Storm Allison in 2001. It shows that El Nino does have an impact on spring rainfall,whether is strengthening or dying. Interesting to note hurricanes made hurricanes made landfall on Upper Texas Coast in 1900, 1929, and 1957. Two were major hurricanes, Galveston Hurricane and Audrey in 1957.

Could this be a harbinger of things to come? America has not seen a Category 3 or stronger hurricane since Wilma in 2005. Now, if we lowered Category 3 by 1 mph from 111 mph to 110 mph, than Ike would be a major hurricane. Even than, America has not seen a major hurricane make landfall since 2008, which is a long stretch. Keep in mind, hurricane re-analysis is happening, so this long stretch of no Category 3 or stronger hurricanes we are seeing may not be the longest.

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Weather In Review And Forecast For May 31, 2015

20150526_South_Plains_NEXRAD_0430Z

Last week was quite a weather week no one will forget in Texas. Wave after wave of heavy rain and severe thunderstorms plagued Texas. Memorial Day had heavy rain in Central and Southeast Texas. The rain over Houston area proved to be catastrophic as many areas saw 8 to 12 inches of rain on Memorial Day night into the small hours of May 26th. A lot of rain and thunder from that storm. It led to flooding in the Houston area as streets are overloaded with water and bayous are above flood stage. As of June 1, 2015, 31 people have died from flooding in Texas. Here is a rainfall total from the Memorial Day event.

20150526_1Day_Rainfall_Total

Many areas in the Austin area saw 3 to 7 inches of rain. Areas southeast of Austin got the heaviest rain in Central Texas, up to 8 inches fell in Bastrop County. Southeast Texas took the brunt of the storm as they stalled out and dumped heavy rain on Memorial Day night into the early morning of May 26th. Many areas in Southeast Texas saw 8 to 12 inches of rain. Many people are comparing the Memorial Day storm to 2001 Tropical Storm Allison. Allison dumped 40 inches on Southeast Texas, including over 28 inches of rain in 12 hours on June 8-9, 2001! That storm claimed 23 lives in the Houston area. Allison went on to ravage the entire Gulf Coast and East Coast of America. Allison claimed 41 lives. Many areas from New Orleans, Mobile, Charlotte, Washington, DC, Philadelphia, New York, and Boston saw heavy rain from Allison.

So, how was Spring like for Texas? Here is a 90 day rainfall total from March 1 to May 31.

20150601_90Day_Rainfall_Total

Many areas in Texas saw over 20 inches of rain! Some saw as high as over 45 inches in North Texas! A weather station in Gainesville, Texas, recorded 28.90 inches of rain for May! Talk about wet! That is almost equivalent to 1 year’s worth of rain for Houston! Houston area saw 20 to 40 inches of rain in Spring! As they say, everything is bigger in Texas! All the rainfall total data is from Advanced Hydrologic Prediction Service (AHPS).

Now, why was it wet this past spring? It must be El Nino and Pacific Decadal Oscillation (PDO). Yup, that is right.

20150601_Global_SST_Anomaly

El Nino is the warm water off the west coast of South America in the Pacific Ocean. It is very warm right now. PDO is the area of warm water off the West Coast of America. When both are in warm phases, that means there is more moisture from the Pacific on top of the abnormally warm Gulf of Mexico. A warm Gulf of Mexico produces more moisture for Texas. Also, jet stream goes further south than usual. That means storms tend track over Texas during El Nino. It would explain the west Spring Texas had.

If El Nino can keep up like this, come Fall and Winter, California and Western US is going to get heavy rain like what Texas had. I would not be surprised if California sees a very wet Winter.

This now leads me to the next thing today. It is the start of the Atlantic Hurricane Season. We already had one named storm, Ana. Here is the remaining names for 2015.

Bill
Claudette
Danny
Erika
Fred
Grace
Henri
Ida
Joaquin
Kate
Larry
Mindy
Nicholas
Odette
Peter
Rose
Sam
Teresa
Victor
Wanda

With El Nino in place, I forecast a less active season for 2015. However, I am not ruling out a landfall of a Category 3 or above on the US coast. It has been 10 years since the last Category 3 hurricane made landfall, which was Wilma on October 24, 2005. You can read more about my forecast.

Weather In Review And Forecast For May 17, 2015

Flood were the main problem last week. Southeast and South Texas saw a lot of rain last week. Many areas saw rain amounts of over 10 inches! The forecast models did not handle the event well. It comes to show that forecasting flood events is difficult. We have a long way to go. Here is the 7 day rainfall total.

20150518_7Day_Rainfall_Total

Many areas saw 5 to 10 inches of rain with isolated totals of over 14 inches of rain! That is a lot in 7 days! So, how wet has it been in the past 30 days?

20150518_30Day_Rainfall_Total

Many areas of Texas and Oklahoma have seen 7 to 15 inches of rain in the past 30 days. Some have seen over 22 inches! That is mostly in North Texas, Red River, and Central Oklahoma. They were dry not too long ago and now they are wet. That is a good thing as Texas and Oklahoma have been plagued by droughts. Let’s hope California gets a lot of rain as well. They need the rain as much as we do. I will gladly donate the rain to California!

So, why has it been so wet lately for Texas and Oklahoma?

20150518_500mb_GeopotentialHeightAnomaly_NH

Persistant upper level troughing over the Western US with persistant upper level ridging over the Eastern US. This type of setup is favorable for severe weather and flood events as the bring in moisture from Gulf of Mexico and Tropical Pacific. There is also El Nino.

20150518_SST_GlobalAnomaly

The area of unusually warm water in the Equatorial Pacific off the coast of South America is El Nino. It is a strong El Nino. El Nino causes the jet steam to go further south than usual. This brings in storms further south, allowing severe weather and heavy rains to fall over Texas and Oklahoma. Also, California benefits from El Nino.

Since my analog forecast from last week suggested flooding is an issue, I am going to use it again. Let’s start with the 6 to 10 day analog forecast.

20150518_6To10Day_AnalogForecast

6/12/1988-Severe weather plagues Texas in June. A F3 tornado strikes 4 miles south of Denver on 6/15.
6/2/1989-Two tornadoes in Louisiana and Florida claim 5 lives on 6/8.
6/2/1978-Heavy rain falls in the Houston area from 5/29 to 6/7. Bush Intercontinental: 12.35″; Hobby: 5.46″. Houston records its wettest 6/6 and 6/7. The rainfall total for those dates are 2.66″ and 2.29″
5/19/1963-Heavy rain falls in parts of Houston on 5/22. Houston WB: 3.10″; Hobby: 0.05″. Houston records its wettest 5/22.
6/4/1966-June 1966 Tornado Outbreak Sequence from 6/2-12. There are 57 tornadoes, which claim 18 lives. One tornado hits Topeka, Kansas on 6/8 as a powerful F5 tornado. It claims 16 lives.
6/12/1969-Tornado outbreak on 6/22. Two F4 tornadoes hit south of St. Louis claiming 6 lives in Washington County and south of Farmington. A F2 tornado hits Oxford, Nebraska claiming 1 life.
6/8/2003-2003 South Dakota Tornado Outbreak. 67 tornadoes touchdown in one day on 6/24 in South Dakota. Nebraska is hit by severe weather on 6/22. Aurora sees volleyball sized hail. A tornado to the south of Aurora claims 1 life. A total of 125 tornadoes are reported in the outbreak.
5/17/1961-Severe weather outbreak on 5/12 to 5/19 in Central and Southern US. Multiple tornadoes, strong wind, and hail reported. No fatalities are reported.
6/2/2000-Remnant of Tropical Depression 1 dumps heavy rain over Texas on 6/9 to 6/11.

Looking at the analog dates, this suggest that we could see heavy rain that could lead to flooding mixed with severe weather like tornadoes, hail, and strong winds. Let’s look into next week with the 8 to 14 day analog forecast.

20150518_8To14Day_AnalogForecast

6/4/1989-Two tornadoes in Louisiana and Florida claim 5 lives on 6/8.
6/13/1988-Severe weather plagues Texas in June. A F3 tornado strikes 4 miles south of Denver on 6/15.
6/1/1978-Heavy rain falls in the Houston area from 5/29 to 6/7. Bush Intercontinental: 12.35″; Hobby: 5.46″. Houston records its wettest 6/6 and 6/7. The rainfall total for those dates are 2.66″ and 2.29″
6/15/2004-All of Texas has a wet June. Many areas see heavy rain that leads to flooding throughout Texas. Tornado outbreak in the Panhandle on 6/21. Large hail reported of diameter of 4.25″.
5/18/1963 & 5/23/1963-Heavy rain falls in parts of Houston on 5/22. Houston WB: 3.10″; Hobby: 0.05″. Houston records its wettest 5/22.
5/17/2004-Heavy rain falls over Central Texas east of Interstate 35 on 5/13. Hearne, Texas records up to 17 inches of rain in a few hours, which leads to severe flooding. May 2004 Tornado Outbreak Sequence from 5/21-31. 389 tornadoes are reported, which claims 7 lives.
5/30/1989-Two tornadoes in Louisiana and Florida claim 5 lives on 6/8.

The 8 to 14 day analog forecast is similar to the 6 to 10 day analog forecast. Mostly heavy rain and severe weather. The June 2004 analog is interesting as Texas had a very wet June. 2004 had a developing El Nino that time. This suggests that as we head into June, it could be a wet June.

With the analog forecasts, this week will be a wet one despite what forecast models have called for recently. I do not trust forecast models when it comes to handling severe weather and heavy rain. It did not handle it well last week. One reason why I am forecasting another wet week this week. Be prepared for any flooding this week!

This Week’s Forecast For Week Of March 15, 2015

Beware of the Ides of March they say. It is also the week of St. Patrick’s Day and March Madness starts. This week should be an exciting week. El Nino has been declared and it could persist for the rest of the year. Before about this week, let’s look at last week’s weather shall we.

20150316_500mb_GeopotentialHeightAnomaly_NH

Most areas were warm last week. The exception are Texas, Alaska, Central Mexico, Northeast Canada, Korea, Japan, North Central Russia, and Eastern Russia, which were cooler than normal. How does this come to be?

20150316_SurfaceTemperatureAnomaly_NH

When it is cooler, there is troughing. When it is warmer, there is ridging. Enough said about that. Troughing over Northeast Canada is negative North Atlantic Oscillation (NAO) and troughing over Alaska is negative East Pacific Oscillation (EPO). The ridging centered over Western US is positive Pacific/North American teleconnection pattern (PNA).

Last week was quite rainy. Here is a 7 day rainfall total from last week up to March 15, 2015.

20150315_7Day_Rainfall_Total

It was very wet in Southeast Texas and Louisiana. The heaviest rain in Southeast Texas is 8 inches, while 10 inches fell in the Mississippi River Delta. Most of Southeast Texas, Southeast Louisiana, and Southern Mississippi got most of the heavy rain last week. Not bad for March. It would be nice to see North Texas and Panhandle get more rain as they are still in a severe drought.

Here is a rainfall forecast model from last week.

20150309_AccumulatedPrecipitationTotal_USA_132Hour_1800Z

It did not get Texas right, while it did handle the Central Gulf Coast okay. These forecast models are not high resolution, so they do not take smaller areas into account.

Rainfall will be the main concern this week as it was last week. Here is a rainfall forecast model til Sunday.

GFS
20150316_GFS_AccumulatedPrecipitationTotal_USA_132Hour_1800Z

Canadian
20150316_GEM_AccumulatedPrecipitationTotal_USA_132Hour_1800Z

Both forecast models have widespread and beneficial rains for Texas and Louisiana. GFS has up to 4 inches for Texas, while Canadian has up to 6 inches of rain in the next 7 days. I think some areas could see higher, like last week. I think some areas could see up to 10 inches of rain in Texas and Louisiana, like last week.

If we could see the future, we could look at the past. In this case, I will be using analog forecasts based on upper air patterns going back to 1950. Let’s start with 6 to 10 forecast.

20150316_6To10Day_AnalogForecast

3/30/1994-A cold blast hits east of the Rocky Mountains in the last week of March 1994.
3/26/1990-Heavy rain hits Houston area between 3/28-30. Three day totals are Bush Intercontinental: 3.61″; Hobby: 2.78″; Galveston: 1.33″.
4/9/2004-Heavy rain falls on 4/10-11 in Southeast Texas. Bush Intercontinental: 3.27″; Hobby: 1.31″; College Station: 0.89″. 2.57″ falls at Intercontinental on 4/10, highest rainfall total for that date.
3/13/1998-Severe weather hits Texas betweem 3/15-19. They range from heavy rain, strong wind, hail, and lightning. It mainly hits North Texas and West Texas. There is snow reported in the Texas Panhandle on 3/19.
4/9/1969-Rain falls 4/11-13 in Houston area. Both Houston WB and Hobby record 2.36″.
4/4/2007-A cold blast hits Texas on Easter Weekend. Snow and sleeted is reported north of Houston. Many areas see near record lows during the cold blast including Houston, which saw 38°F on 4/7 and 37°F on 4/8.
3/11/1987-Cold blast hits Southern and Eastern US between 3/9-15.
4/6/1977-16 tornadoes reported in West Texas and Panhandle between 4/19-20. Hail is also reported during the severe weather outbreak in Texas.

Some of the analog dates really stand out, especially when it comes to cold blasts and severe weather. If we use 6 to 10 day analog forecast, this suggests it could be a rainy one with a chance of severe weather mixed in. Anyways, let’s look at the 8 to 14 day analog forecast. Deja vu, it is wrongly labeled as 6 to 10 day forecast as it centers around day 8. Do not worry, this is a 8 to 14 day analog forecast.

20150316_8To14Day_AnalogForecast

3/31/1994-A cold blast hits east of the Rocky Mountains in the last week of March 1994.
3/25/1990-Heavy rain hits Houston area between 3/28-30. Three day totals are Bush Intercontinental: 3.61″; Hobby: 2.78″; Galveston: 1.33″. Interesting to note on that date, America’s deadliest mass murder occurred on this day at the Happyland Club Fire. A man angry over a break up with his girlfriend set fire to the club in The Bronx borough of New York. The fire claimed 87 lives. It was the deadliest mass murder prior to Oklahoma City Bombing and 9/11.
3/11 & 3/16/1998-Severe weather hits Texas betweem 3/15-19. They range from heavy rain, strong wind, hail, and lightning. It mainly hits North Texas and West Texas. There is snow reported in the Texas Panhandle on 3/19.
3/9/1994-A cold front comes on 3/9 and thunderstorms form ahead. Bush Intercontinental: 1.18″; Hobby: 1.20″; Galveston: 1.26″; Second wettest 3/9 for Bush and Galveston. The cold front brings a light freeze.
3/9/1996-A cold front comes on 3/7/1996. It causes a light freeze for Houston area.

The 8 to 14 day analog forecast has some rather interesting weather. They are either cold blasts to severe weather outbreaks. I think this week is more likely a rain event if any. I do not think temperature will be much of a factor here. This will be another wet week as it was last week thanks to El Nino and strong Madden-Julian Oscillation (MJO).

This Week’s Forecast For Week Of March 8, 2015

20150227_DallasSnow01
Source: Wikimedia

Even with March in, it has been rather cold. North Texas has gotten a lot of snow. It is like that Old Man Winter does not want to leave despite the calendar saying so. Not surprisingly, the coldest air is over North Texas. East of the Rocky Mountains has been cold last week. Alaska and Arctic Ocean have been quite warm.

20150309_SurfaceTemperatureAnomaly_NH

Now, why it is cold in some areas, while warm in others. Look no further than the upper part of the atmosphere.

20150309_500mb_GeopotentialHeightAnomaly_NH

What do I see here? I see upper level ridging over Alaska, which is negative East Pacific Oscillation (EPO). There is upper level troughing over Northeast Canada and Greenland, which is positive North Atlantic Oscillation (NAO). Cold blasts can happen with a negative EPO and positive NAO. There is also upper level ridging over Northern Russia. Ridging over Arctic areas causes cold air to be shunted down south. Troughing keeps the cold air over the Arctic.

This week has started rainy in Texas. Beneficial rain that puts a dent on the drought plaguing Texas. Here is a 132 hour rainfall total forecast til Sunday.

20150309_AccumulatedPrecipitationTotal_USA_132Hour_1800Z

The GFS and Canadian forecast 0.50 to 1.50 inches of rain. The Canadian goes as high as 3 inches of rain between now and Sunday. Rain will be the main headline for the Southeast as the same system over Texas traverses eastward carrying Pacific and Gulf of Mexico moisture. This is more of an El Nino pattern, which we are in. The GFS forecasts less rain for Alabama and Florida Panhandle. On the other hand, Canadian has up 5 inches of rain for Alabama and Florida Panhandle. The GFS has the heaviest rain over Tennessee.

What can the past hold for this week? Here is a 6 to 10 day analog forecast.

20150309_6To10Day_AnalogForecast

3/13/1972-A slow moving cold front triggers heavy rain over Southeast Texas on 3/20. Bush Intercontinental: 7.47″; Hobby: 0.64″; Independent Heights 7.65″; Halls Bayou 9.50″; Galveston: 0.82″; College Station: 0.07″. Record calendar day rainfall total for Bush.
3/1/1994-A cold front comes on 3/9 and thunderstorms form ahead. Bush Intercontinental: 1.18″; Hobby: 1.20″; Galveston: 1.26″; Second wettest 3/9 for Bush and Galveston. The cold front brings a light freeze.
3/24/1993-Southeast Texas saw rain from 3/19 to 3/23. Heavy rain falls on 4/3-4. Bush Intercontinental: 3.68″; Hobby: 2.17″; Galveston: 0.81″. 3.09″ falls at Houston on 3/9, setting highest one day rainfall total for that date.
3/2/1993-Start of the “Storm Of The Century”, also known as ’93 Superstorm. A strong extratropical low pressure system forms in the Gulf of Mexico ahead of a cold front. The storm rapidly intensifies and becomes a large and powerful storm. Derechos and storm surge are experienced in Florida, while Appalachia and Northeast are pelted by heavy snow and blizzard.
3/15/1995-A March heat wave strikes east of the Rocky Mountains and Northern Canada betweem 3/18 to 3/23. Many areas see near or record highs during that time.
3/5/1992-Heavy rain and flooding hits the Houston area on 3/4. Many areas see 4 to 10 inches of rain during the event.

Some of the analog dates really stand out, especially when it comes to heavy rain. One had a unusual March heat wave. If we use 6 to 10 day analog forecast, this suggests it could be a rainy one. Anyways, let’s look at the 8 to 14 day analog forecast. By the way, it is wrongly labeled as 6 to 10 day forecast as it centers around day 8. Do not worry, this is a 8 to 14 day analog forecast.

20150309_8To14Day_AnalogForecast

4/5/2004-Heavy rain falls on 4/10-11 in Southeast Texas. Bush Intercontinental: 3.27″; Hobby: 1.31″; College Station: 0.89″. 2.57″ falls on 4/10, highest rainfall total for that date.
4/4/2007-A cold blast hits Texas on Easter Weekend. Snow and sleeted is reported north of Houston. Many areas see near record lows during the cold blast including Houston, which saw 38°F on 4/7 and 37°F on 4/8.
3/5/1984-March 1984 starts cold with a low of 31°F at Bush Intercontinental on 3/1.
3/29/1993-Southeast Texas saw rain from 3/19 to 3/23. Heavy rain falls on 4/3-4. Bush Intercontinental: 3.68″; Hobby: 2.17″; Galveston: 0.81″. 3.09″ falls at Houston on 3/9, setting highest one day rainfall total for that date.

In the long term analog, heavy rain or cold blasts are the issue. There was a cold Easter in 2007. If I use the 6 to 10 day and 8 to 14 day analog forecast, it looks to be cooler and wetter than normal for the start of March.

This Week’s Forecast For Week Of March 1, 2015

20150302_SurfaceTemperatureAnomaly_NH

Finally, we are no longer in the meteorological winter. We are in spring, which is from March to May. Last week, the nation was more unified. Unified in the sense of temperature. Most of the US east of the Rocky Mountains had colder than normal temperatures. It snowed and iced in North Texas. The Northeast and Midwest languished in freezes. Even the Western US had more normal temperatures instead of a summer. Of course with all the cold air over the Lower 48, it is much warmer in Alaska and Northwest Canada. All the cold air had to go somewhere and it happens to be us. So, why the cold weather in some areas, while warm weather in others. It is has to do with the upper level pattern.

20150302_500mb_GeopotentialHeightAnomaly_NH

There is upper level troughing over Northeast Canada and Greenland, which is a positive North Atlantic Oscillation (NAO). It is also the polar vortex, which brings down cold air from Arctic. The upper level ridging over Alaska is the negative East Pacific Oscillation (EPO). The ridging causes cold air to be shunted down south. Freezes can happen when there is a positive NAO and negative EPO, like in January 1962, December 1983, and February 1989.

Here is a 6 to 10 day analog forecast.

20150302_6To10Day_AnalogForecast

2/27/2009-A late February heat wave hits the South and Northeast US. Houston records a high of 85°F on 2/27/2009. Second hottest 2/27 on record.
3/16/1978-A cold mid March cold blast hits east of the Rocky Mountains and Eastern Canada. Houston records a low of 33°F on 2/27/2009.
3/8/1982-A cold early March cold blast hits east of the Rocky Mountains and East Central Canada. Northern New England and Maritime Provinces of Canada are warmer than normal. Houston records a low of 30°F on 3/7/1982.

Some of the analog dates for the 6 to 10 day forecast stands out. Those dates had a cold blast right before or after the date. One of them was a warm one in 2009. Now, let’s look at 8 to 14 days analog forecast.

20150302_8To14Day_AnalogForecast

3/7/1989-America sees an early March cold blast. Houston sees 25°F on 3/5 and 3/6 and 28°F on 3/7, shatter low temperature records for those dates. Night time sees freezes from 3/4 to 3/9.
2/26/1974-A late February cold blast hits America in a La Nina Winter. Houston sees 26°F on 2/25 and 2/26, which are record lows for those dates.
2/23/1976-A late February cold blast hits America in a La Nina Winter. Houston sees 27°F on 2/23, which is a record lows for those dates.
3/26/1982-As El Nino is developing, Southern US is hit by a heat wave in April. Houston records a high of 91°F on 4/5/1982 and 4/8/1982, warmest for 4/5. That week is a roller coaster ride of warm and cold.

Some of the analog dates for the 8 to 14 day forecast stands out. There were mostly cold blasts in some of the dates I listed. One had a heat wave in April, which gave way to cold again. I can this week as a roller coaster as it warms up and cools down. Here are temperature forecast model by Friday of this week.

20150303_2MeterAirTemperature_84Hour_0000Z

GFS and NAM are not much different as they have a low of 28°F to 29°F on Friday morning. The Canadian is the warmest at 31°F. That is quite cold for this time of year for Southeast Texas! I think it will be cold this week. Freezing rain and snow is not out of the realm for sure. This is going to be an interesting week.

Spring 2014 Report

Spring2014Ranks

Spring has passed as we approach summer as the days get longer. So, did winter choose to remain despite the fact the calendar says spring? Some areas were still cold and ice still prevailed in the Great Lakes. It was warm in the Western US as they are still languishing in a drought.

America
Temperature: 51.13°F
Rainfall: 8.01

1895-2014 Spring Statistics
Spring Temperature Mean: 51.06°F
Spring Temperature Median: 50.82°F
Standard Deviation: 1.36

Spring Rainfall Mean: 7.93
Spring Rainfall Median: 7.91
Standard Deviation: 0.97

America as a whole had a largely normal spring because of the stark contrast in temperature and rainfall. Some regions were cooler, while others were warmer. In terms of rain, some regions got more, while others got less. So that cancels each other out. This surface temperature anomaly map shows the eastern half of the US was cooler, while western half of the US was warmer. Most of the cold air was over Canada and Upper Midwest. Most of Arctic, Asia, and Europe had warmer than normal spring.

2014SpringSurfaceTemperatureAnomaly

One wonders why was the Eastern US cooler than the Western US this past spring. Look at a 500 millibar level geopotential height to look for anomalies. A positive anomaly is persistent ridging, while negative anomaly is persistent troughing. Here is a map of the 500 millibar level geopotential height anomaly map.

2014Spring500mbGeopotentialAnomaly

The North Atlantic Oscillation (NAO) is in a positive phase, as there is persistent troughing over Greenland and Northeastern Canada. A positive NAO usually means warmer than normal winter when NAO is positive. However, there is persistent ridging over Alaska. That area is called Nort Pacific Oscillation (NPO) or East Pacific Oscillation (EPO). When there is ridging over Alaska, the NPO/EPO is negative, while troughing over Alaska means positive NPO/EPO. The NPO/EPO is similar to NAO, but over the North Pacific Ocean. A negative NPO/EPO gives America a cooler than normal winter. It can have much influence than NAO, like this past winter, which was a cold one. Another cold winter where the NAO was positive, but NPO/EPO was negative is the winter of 1983-1984. That winter was really cold, especially December 1983.

Now, let’s look at the great state of Texas’s spring.

Texas
Temperature: 64.13°F
Rainfall: 6.12

1895-2014 Spring Statistics
Spring Temperature Mean: 64.75°F
Spring Temperature Median: 64.73°F
Standard Deviation: 1.77

Spring Rainfall Mean: 7.26
Spring Rainfall Median: 7.05
Standard Deviation: 2.16

Like America, Texas had a normal spring in terms of temperature and rainfall. The temperature is below average, but within average. Texas saw normal March rainfall as it got beneficial rains to put a dent on the drought. However, Texas needs more rain to end this drought, which will hopefully be case with El Nino. So, how did Houston area fared in Spring.

Upper Texas Coast
Temperature: 66.93°F
Rainfall: 11.12

1895-2014 Spring Statistics
Spring Temperature Mean: 68.50°F
Spring Temperature Median: 68.39°F
Standard Deviation: 1.68

Spring Rainfall Mean: 10.38
Spring Rainfall Median: 9.91
Standard Deviation: 4.28

It is not your imagination that Spring 2014 was cool in Southeast Texas. It was cooler than normal despite the fact that Texas and America had normal spring. The Upper Texas Coast cracked the top 20 coolest spring on record. It is even cooler than Spring 2013. Winter prevailed in Spring 2014 for Upper Texas Coast. This is despite the fact it is within the mean, but close enough to be outside the mean to be considered abnormal. Here is the top 20 coolest spring in the Upper Texas Coast.

Top 20 Coldest Spring
1.) 1931 63.37°F
2.) 1915 64.87°F
3.) 1926 65.53°F
4.) 1913 65.63°F
5.) 1983 65.67°F
6.) 1914/1969 65.87°F
7.) 1952 65.90°F
8.) 1924/1960 66.07°F
9.) 1941 66.40°F
10.) 1947 66.53°F
11.) 1970/1993 66.57°F
12.) 1912 66.60°F
13.) 1919 66.63°F
14.) 1917 66.67°F
15.) 1932 66.77°F
16.) 1942 66.83°F
17.) 1937 66.90°F
18.) 2014 66.93°F
19.) 1928/1962 67.03°F
20.) 1930 67.07°F

Spring 2014 is the 18th coolest spring on record since 1895! Spring 2013 is 22 coolest spring on record and ties with Spring 1901 as the average was 67.13°F. Interesting to note following a cool spring, a major hurricane has made landfall on the Upper Texas Coast in these years. Here are the correlation values between Spring Temperatures (March to May) and tropical landfall on the Upper Texas Coast.

Tropical Storm
r = 0.03
p = 0.71

Hurricane
r = 0.11
p = 0.22

Major Hurricane
r = -0.21
p = 0.02

All Landfall
r = 0.00
p = 0.99

There is a significant negative correlation between cool springs and major hurricanes making landfall on the Upper Texas Coast. Cooler the spring, the more likely a major hurricane is likely to make landfall. It is significant because the p-value below 0.05. Anything above 0.05 is not significant. Four of the top 20 coolest spring had a major hurricane make landfall during the hurricane season from June to November.

Major Hurricane
1915-Galveston Hurricane of 1915 (Category 3)
1932-Freeport Hurricane (Category 4)
1941-Hurricane #2 (Category 3, Based on Reanalysis)
1983-Alicia (Category 3)

Hurricanes
1947-Hurricane 3 (Category 1)

Interesting to note that San Antonio Spurs won the NBA Championship, a hurricane made landfall. Here are the championship years for Spurs and hurricanes that made landfall.

1999-Bret
2003-Claudette
2005-Rita
2007-Humberto
2014-?

Two are Category 3 or above, while the other two are Category 1. In Humberto’s case, had it stayed over the Gulf of Mexico longer, it easily would have been a Category 3 or above hurricane. Thankfully that never happened as it made landfall east of Galveston on September 13, 2007 at 2:00 AM. Eerily, exactly one year later on that day and time, a much larger hurricane, Hurricane Ike, made landfall on the eastern part of Galveston Island.

However, none of them had an El Nino developing that year. Most were either Neutral (2003) or going into La Nina (1999, 2005, and 2007). El Nino is forecasted to develop for this year and that reduces storm formation from westerly wind shear. However, during El Nino years, storms form closer to land and increase their chance for landfall. My spring forecast for the 2014 Atlantic Hurricane Season used years that saw El Nino developing early. Looking at it this 2014 analog GIS heat map, many of them end up in the Gulf of Mexico, particularly the Central and Western Gulf of Mexico.

2014AnalogHurricaneHeatMap

Notice the highest risk for storms to hit are the Central Gulf Coast region, which is Louisiana, Mississippi, and Alabama. Southeast Texas is also in a high risk area for landfall during an analog season where El Nino is developing. It proves that even a less active season is just as dangerous as an active season.