Archive for the ‘USA case studies’ Category

Historic summer-like heat wave across parts of North America, numerous records!

The first two decades of March were simply said EXTREME of extremes as regarding the warmth across much of the E-CNTRL CONUS as well as parts of SE Canada. Numerous stations broke their all time March records, some of them reached even values which are records for month of April. Extreme warmth, at least to say! Below are some details about these last 3 weeks across the North America…

The main cause for such a remarkable summer-like warmth (“heat wave”) in the early spring was the large blocking pattern across the eastern CONUS while the western CONUS was under a deep long-wave trough. In between, a very warm airmass was advecting northwards across the US.

An aforementioned pattern persisted for almost 3 weeks and resulted in extreme positive height/temp anomaly across the North America. Here is a reanalysis map showing the H5 anomaly between March 1st and March 22nd 2012:

The SFC temp anomaly for the same period is impressive as well… the areas from E NE across IA/IL/S MN into Great Lakes and SSE Canada experienced above 8°C (K) too warm average temperature:

And finally, the SFC temp anomaly during the peak “heat wave” between March 15th and 22nd 2012, once again… that is simply said extreme! It never happened before in March! large parts of MN/IA, WI, northern IL/IN/OH, Great Lakes and SE Canada experienced extremely warm temperatures for mid March, average 8-day temperature was remarkably 15°C or more higher than average!

A SFC temp anomaly between 8-15th March, notice the very extreme anomaly across the N-CNTRL US and further north across S-CNTRL Canada!

Its hard to pinpoint all the broken records as there were thousands daily records and numerous all time records as said before. So here are just the most remarkable ones… the all-time March monthly heat records were broken at these stations:

NORTH DAKOTA

Bismarck 81° 3/16 (ties old record several occasions)

SOUTH DAKOTA

Pierre 88° 3/18 (old record 87° several occasions)

A reading of 94° was reported from Winner on 3/18. This is the warmest reading recorded during the heat wave at any location, but short of the South Dakota March record of 96° set at Tyndall in March 1943.

MINNESOTA

Int’l Falls 79° 3/18 (old record 73° on 3/31/1963)

WISCONSIN

Madison 83° 3/21 (old record 82° several occasions)
Milwaukee 84° 3/21 (old record 83° on 3/20/2012)
Green Bay 82° 3/21 (ties old record on 3/29/1910)

ILLINOIS

Chicago fell short 1° of record (88° 3/31/1986) with 87° on 3/21

MICHIGAN

Saginaw 87° 3/21 (old record 83° 3/24/1910)
Detroit 86° 3/22 (old record 82° 3/28/1945)
Flint 86° 3/21 (old record 83° 3/22/1938)
Traverse City 87° 3/21 (old record 82° 3/29/1910)
Grand Rapids 87° 3/21 (old record 82° 3/29/1910)
Lansing 86° 3/21 (old record 82° 3/24/1910)
Marquette 81° 3/21 (old record 71° 3/8/2000) *Marquette’s record heat anomaly is almost beyond belief as can be read in this report. Their 47” snow pack on March 5th melted away to nothing in just two short weeks.
Muskegon 82° 3/21 (old record 80° 3/31/1981)
Sault Ste. Marie 83° 3/21 (old record 75° 3/28/1946)
Alpena 87° 3/21 (old record 80° 3/8/2000)

NOTE: Basically, every site in Michigan broke their March heat record during this event. The list of cities is too long to include all herein. The state record for March was broken at Lapeer on 3/21 when a reading of 90° was measured (previous record was 89°, also at Lapeer in 1910).

INDIANA

Fort Wayne 87° 3/21 (old record 3/24/1910)
South Bend 85° 3/21 (ties 3/31/1981)

OHIO

Cleveland 83° 3/21 (ties old record set in 3/28/1945)
Akron 83° 3/22 (old record 82° 3/24/1910)
Mansfield 84° 3/22 (old record 82° 3/30/1986)
Toledo 85° 3/21 (old record 83° 3/24/1910)
Columbus 85° 3/22 (old record 82° 3/24/1910)
Dayton 86° 3/21 (old record date unknown)

NEW YORK

Buffalo 82° 3/21 (old record 81° 3/28/1945)

VERMONT

Springfield reached 83° on 3/22. One degree short of the state March heat record.

NEW HAMPSHIRE

Berlin 80° 3/22 (tied with 3/30/1998)
First Connecticut Lake 77° 3/22 (old record 73° date NA)

MAINE

Caribou 75° 3/21 (old record 73° 3/30/1998)
Houlton 79° 3/21 (old record 72° 3/30/1998)
Bangor 84° 3/22 (old record 79° 3/29/1946)

CANADA

Historical weather records for March heat were smashed over a large portion of eastern Canada. Here are a few of the highlights:

Ottawa, Ontario 27.4°C (81.3F°) 3/21 (old record 26.7°C/80.1°F 3/29/1946
Windsor, Ontario 27.0° (80.6F°) 3/21 (old record 26.6°C/79.9°F 3/28/1945)
Kapuskasing, Ontario 26.2°C (79.2F°) 3/20 (old record 19.4°C/66.9° 3/25/1945)
Winnipeg, Manitoba 24.0°C (75.2°F) 3/19 (old record 23.3°C/73.9°F 3/27/1946)
Montreal, Quebec 25.8°C (78.4F°) 3/21 (old record 25.6°C/78.1°F 3/28/1945)
Quebec City, Quebec 18.3°C (64.9F°) 3/21 (old record 17.8°C/64.0°F 3/30/1962)
St. John, New Brunswick 27.2°C (81.0F°) 3/21 (old record 16.8°C/62.2°F 3/29/1999)
Halifax, Nova Scotia 27.2°C (81.0°F) 3/22 (old record 25.6°C/78.1°F 3/31/1998)

At St. John this March record was warmer than their all-time April monthly heat record!

Western Head, Nova Scotia recorded 29.2°C (84.6°F) on 3/22, the warmest temperature ever recorded in March in Nova Scotia and the 3rd warmest March temperature on record for all of Canada. It surpassed its previous daily record high of 10.6°C (51.1°F) by an astonishing 18.6°C (33.5°F)!

Here are additional stats which are going off imagination when you make the comparisons. Some stations broke their previous high max temperatures with their minimum temperature on specific days this year, extremely unusual at least to say!

The low temperature at Marquette, Michigan hit 52° on March 21, which was 3° warmer than the previous record high for the date.

The low at Mt. Washington, NH on March 21 (44°) beat the previous record high for the date (43°.)

The low temperature for International Falls, Minnesota on March 20 bottomed out at 60°F, tying the previous record high for the date.

The low temperature in Rochester, Minnesota on March 18 was 62°F, which beat the previous record high for the date of 60°.

Several stations in Canada broke even an April month records with temperatures reached in March! Here are the two most extreme ones…

St. John, New Brunswick hit 27.2°C (81°F) on March 21. Previous March record: 17.5°C on March 21, 1994. April record: 22.8°C.

Kejimkujik Park, Nova Scotia hit 27.9°C on March 21. Previous March record: 22.5°C on March 30, 1986. April record: 25°C on April 27, 1990.

Halifax, Nova Scotia hit 27.2°C (81°F) on March 22, 2012. Previous March record: 25.8°C set the previous day. April record: 29.5°C, set on April 28, 2009.

Here is one interesting comparisons, showing the snow depth across MN starting on March 1st and ending on March 22nd. Notice how much snow was melted in NE corner, from around 25-30″ down to zero in only 3 weeks! One have to aware that this is mid March when usually there is still a lot of snow so far north along the US/Canada border. So as for now, there is no snow left in MN/ND and other states nearby.

More detailed daily statistics for several cities can be found below:

Minneapolis/St. Paul, MN…

St. Cloud, MN…

Eau Claire, WI…

Chicago, IL…

And here is a table of daily broken records at Chicago O’Hare International airport day by dath in the mid March…

Sources:
NWS Chicago, IL
NWS Milwaukeee/Sullivan, WI
Wunderground – Christopher C. Burt
Wunderground – dr. Jeff Masters

Stay tuned!


Large upper low crosses CONUS and results in high precip sums over southern US!

During the past several days, an intense upper low was slowly moving across the CONUS as it ejected from the unusually deep trough over western US earlier this week. Models were confidently predicting large precip sums especially over the southern Plains towards the lower MS valley. The low was nicely visible on WV satellite while progressing across the CONUS.

Below are short analyses starting on Mon 19th, when the upper low was about to cut off from the main trough. On 20th of March, the upper low was centered over W TX. At surface, an intense cold front was slowly moving from E TX into W LA and GoM where very intense rainfalls were observed. This same frontal system spawn a couple of tornadoes in SW TX around San Antonio a day earlier, Mon March 19th.

1728 2 ENE GARDENDALE ECTOR TX 3203 10234 *** 3 INJ *** TORNADO TOUCHED DOWN APPROXIMATELY 2 MILES ENE OF GARDENDALE AND TRANSLATED NE FOR APPROXIMATELY 1 MILE. MAXIMUM WIDTH APPROXIMATELY 50 YARDS. A BARN … A (MAF)

2325 2 S ELYSIAN WASECA MN 4417 9368 EFO TORNADO BEGAN APPROXIMATELY 2 MILES SOUTH OF THE CITY OF ELYSIAN NEAR THE NORTHEASTERN SHORE OF LAKE ELYSIAN. IT PROCEEDED NORTH FOR SEVEN MILES MARCHING PAST THE W (MPX)

0106 2 SSW LYTLE MEDINA TX 2921 9881 POWER FLASHES AND OVERTURNED SEMI TRAILER AT I-35 MILE MARKER 127. (EWX)

0120 3 NNW DEVINE MEDINA TX 2919 9893 POWERLINES KNOCKED DOWN AT COUNTY ROAD 664 AND 5710 NEAR DEVINE. (EWX)

0130 2 ESE LACOSTE BEXAR TX 2930 9878 POSSIBLE TORNADO DAMAGE OF 6 HOMES ON TED WILLIAMS AND OBRIEN ROAD … AND LADD ROAD. TWO NON-LIFE THREATENING INJURIES WERE REPORTED. (EWX)

0250 UNIONTOWN CRAWFORD AR 3558 9444 PRELIMINARY EF-1 TORNADO DAMAGE FROM SW OF UNIONTOWN TO NE OF CEDARVILLE. TIME ESTIMATED. (TSA)

Detailed reports: SPC reports 12/03/19

A WV satellite and radar scan showing squall-line across the E TX on March 20th…

Here are the storm reports from 20th…

Time Location County State Lat Lon Comments

1635 2 NE ZWOLLE SABINE LA 3166 9362 POSSIBLE TORNADO. MULTIPLE TREES AND POWERLINES DOWN ALONG HWY 1215 AND 120 NEAR THE BELMONT AREA. (SHV)

1641 5 E ZWOLLE SABINE LA 3164 9356 AN EF0 TORNADO TOUCHED DOWN ALONG HWY. 1215. SEVERAL TREES WERE SNAPPED AND UPROOTED AND A FEW POWERLINES WERE DOWNED. THE TORNADO CONTINUED NORTHEAST CROSSING HWY. 120 (SHV)

1815 GOLDONNA NATCHITOCHES LA 3202 9291 TREES DOWN AND POWER OUTAGES REPORTED ON HWY 156 NEAR GOLDONNA (SHV)

1818 2 SE GOLDONNA WINN LA 3200 9289 AN EF0 TORNADO TOUCHED DOWN ALONG STATE ROUTE 156. SEVERAL TREES WERE SNAPPED ON BOTH SIDES OF THE ROAD WITH POWERLINES DOWNED. MORE TREES WERE DOWNED ON RAILROAD TRACK (SHV)

0229 2 E NATCHITOCHES NATCHITOCHES LA 3176 9306 AN EF0 TORNADO TOUCHED DOWN NEAR THE CEDAR GROVE MOBILE HOME PARK. A TREE WAS SNAPPED ALONG HWY. 484 LEADING EAST INTO THE MOBILE HOME PARK. 3 HOMES SUSTAINED DAMAGE WI (SHV)

0815 2 S SIKES WINN LA 3205 9249 AN EF0 TORNADO BRIEFLY TOUCHED DOWN ALONG HWY. 499. A FEW TREES WERE SNAPPED ON THE WEST SIDE OF THE HWY. NEAR PARISH ROAD 1134 AND HWY. 499 INTERSECTION. THE TORNADO W (SHV)

0930 LAKE ARTHUR JEFFERSON DAVIS LA 3008 9268 NWS STORM SURVEY CONFIRMS AN EF 1 TORNADO TOUCHDOWN JUST SOUTH OF LAKE ARTHUR. THE TORNADO TRAVELED NORTH THROUGH THE CITY OF LAKE ARTHUR ON A TWO MILE LONG PATH. PATH (LCH)

0945 1 S GUEYDAN VERMILION LA 3001 9251 NWS STORM SURVEY CONFIRMS AN EF 1 TORNADO TOUCHDOWN ONE MILE SOUTH OF GUEYDAN ALONG LA 91. THE TORNADO TRAVELLED 2.5 MILES WITH A WIDTH OF 40 YARDS. DAMAGE INCLUDED A T (LCH)

1035 1 W HENRY VERMILION LA 2988 9210 NWS STORM SURVEY CONFIRMED AN EF 0 TORNADO TOUCHDOWN ABOUT ONE AND A HALF MILES WEST OF HENRY. PATH LENGTH WAS 1 MILE AND PATH WIDTH WAS 20 YARDS. DAMAGE INCLUDED A ROO (LCH)

1045 ABBEVILLE VERMILION LA 2997 9212 NWS STORM SURVEY CONFIRMED AN EF 1 TORNADO TOUCHDOWN ALONG RICE COVE AND CHAISSON ROADS. THE PATH WAS 1.5 MILES LONG AND THE PATH WIDTH WAS 20 YARDS WIDE. A GARAGE WAS (LCH)

Detailed reports: SPC reports 12/03/20

On March 21st, the upper low moved further NE and was centered over W OK, the cold front with intense squall line was pushed further into lower MS valley.

A view from WV and VIS satellite channels…

Additionally, several tornadoes were reported from E LA and W MS. Here are the storm reports from 21st…

Time Location County State Lat Lon Comments

1257 PATTERSON ST. MARY LA 2969 9131 NWS STORM SURVEY CONFIRMED AN EF0 TORNADO WITH A PATH ONE MILE LONG AND FORTY YARDS WIDE. A FEW TREES HAD LIMBS SNAPPED OFF. A LARGE INDUSTRIAL BUILDING HAD ITS GARAGE (LCH)

1330 2 W GRAYSON CALDWELL LA 3205 9215 POSSIBLE TORNADO DAMAGED ABOUT 20 HOMES … AND DOWNED NUMEROUS TREES ALONG HWY 126 ABOUT 2 MILES WEST OF GRAYSON. (SHV)

1338 2 W GRAYSON CALDWELL LA 3205 9215 AN EF1 TORNADO TOUCHED DOWN ALONG STATE ROUTE 845 SNAPPING A FEW TREES. THE TORNADO CROSSED HWY. 126 ALONG MCCRARY RD. WHERE MOST OF THE DAMAGE OCCURRED. 20 HOMES WERE (SHV)

1434 PRAIRIEVILLE ASCENSION LA 3030 9097 NWS STORM SURVEY TEAM CONFIRMED A TORNADO TOUCHED DOWN AND TRACKED THROUGH PORTIONS OF PRAIRIEVILLE. THE TORNADO INITIALLY TOUCHED DOWN ALONG DUPLESSIS RD … TRACKED APP (LIX)

1500 WENONA WASHINGTON NC 3573 7663 A VERY WEAK AND BRIEF TORNADO TOUCHED DOWN NEAR WENONA THIS MORNING. THE TORNADO WAS SPOTTED IN AN OPEN FIELD AND DID NO DAMAGE. THIS TORNADO WAS NOT ASSOCIATED WITH A (MHX)

1523 1 E MCNAIR JEFFERSON MS 3164 9102 NWS STORM SURVEY TEAM CONFIRMED AN EF1 TORNADO WITH MAXIMUM WINDS OF 94 MPH IN JEFFERSON COUNTY. THE TORNADO TRACKED 3 MIILES ALONG A PATH WHICH BEGAN 1 MILE EAST OF MC (JAN)

1551 8 S VICKSBURG WARREN MS 3221 9087 TORNADO BEGAN 8.5 MILES NNE OF PORT GIBSON AND ENDED 8 MILES SOUTH OF VICKSBURG. TWO MOBILE HOMES DESTROYED, 3 OUTBUILDINGS DESTROYED AND ONE HOUSE HAD MAJOR ROOF DAMAG (JAN)

1554 3 SE YOKENA WARREN MS 3214 9090 NUMEROUS REPORTS OF TREES AND POWERLINES DOWN WITH NUMEROUS ROADS BLOCKED. MEMA STAFF ON SCENE REPORTS NUMEROUS TREES DOWN IN PATTERN THAT SUGGESTS A TORNADO … AND RADA (JAN)

1611 2 SSE VICKSBURG WARREN MS 3230 9086 THIS TORNADO OVERTURNED TWO TRAILERS … SNAPPED TREES AND PEELED PART OF A MEDAL ROOF OFF A BUILDING AT THE ARMY CORPS OF ENGINEERS EXPERIMENTAL STATION. THE TORNADO WAS (JAN)

1716 3 NE MADISONVILLE ST. TAMMANY LA 3043 9013 A NWS STORM SURVEY TEAM OBSERVED DAMAGE PRODUCED BY A TORNADO NORTHEAST OF MADISONVILLE. THE TORNADO TOUCHED DOWN NEAR THE CLUB HOUSE IN TCHEFUNCTA COUNTRY CLUB ESTATES (LIX)

1907 2 WSW PELAHATCHIE RANKIN MS 3231 8984 ROOF COMPLETELY OFF OF A FRAME HOME AND NUMEROUS TREES DOWN ALONG US HIGHWAY 80. LIKELY TORNADO BASED ON RADAR. (JAN)

2100 2 SE EASTABUCHIE FORREST MS 3141 8926 TORNADO SNAPPED A NUMBER OF TREES ALONG A PATH FROM LONGLEAF DR ACROSS EASTABUCHIE ROAD. MINOR DAMAGE OCCURRED TO THE ROOF OF A HOME AND FENCE WAS DAMAGED BY A TREE FAL (JAN)

2231 3 WSW SOSO JONES MS 3173 8932 NWS SURVEY TEAM DETERMINED THAT DAMAGE TO A CHICKEN FARM ON HUEY P ROAD WAS THE RESULT OF A BRIEF TORNADO TOUCHDOWN. ONE CHICKEN HOUSE ROOF WAS HEAVILY DAMAGED AND A TR (JAN)

0132 12 NW LONG BEACH HARRISON MS 3048 8931 NWS SURVEY CONCLUDED AN EF0 TORNADO 50 YARDS WIDE WAS ON THE GROUND FOR 1/4 MILE. WINDS ESTIMATED AT 70 MPH. DAMAGE TO A TRAILER AT VIDALIA AND WALNUT ROADS. (LIX)

0203 2 ESE PAULDING JASPER MS 3202 8901 NWS STORM SURVEY DETERMINED PATH OF TREES SNAPPED AND UPROOTED ALONG COUNTY ROADS 16 AND 503 WAS AN EF-0 TORNADO. PATH LENGTH 0.5 MILES … MAX WIDTH 75 YD … MAX ESTIMATE (JAN)

0535 15 NNE GULFPORT HARRISON MS 3059 8897 NWS STORM SURVEY CONFIRMED A TORNADO TOUCHED DOWN ON JOHN LEE ROAD AND ROBERTS ROAD. TREES WERE TWISTED … A TRAVEL TRAILER WAS FLIPPED … AND SEVERAL HOMES LOST A PORT (LIX)

1010 5 N BILOXI HARRISON MS 3049 8893 NWS STORM SURVEY CONFIRMED A TORNADO TOUCHED DOWN ALONG HWY 67 AT HWY 15. MOST OF THE DAMAGE WAS AT THE STARTING POINT WITH A LARGE SHED DOOR BLOWN IN CAUSING ROOF DAMA (LIX)

Detailed reports: SPC reports 12/03/21

On March 22nd an upper low moved into S KS, the main cold front ejected into SE States out of the main jet stream and didn’t produce anything too severe there, the front slowly dimished. On the back side of the upper low, rainfall were expanding into SW KS as well and TX Panh later on. Meanwhile the upper low was very well visible also on VIS satellite, here is one of the scans…

On March 23rd, the low moved into the TN/OH valley and caused an outbreak of severe storms on its front flank across IL/IN/OH states.

Time Location County State Lat Lon Comments

1429 2 SSW TROY MUNICIPAL AI PIKE AL 3183 8602 TORNADO REPORTED BY TROY AIRPORT WEST OF THE AIRPORT MOVING TOWARD THE AIRPORT. (BMX)

1434 1 S TROY MUNICIPAL AIRP PIKE AL 3185 8601 HOUSE AND BARN SUSTAINED DAMAGE ALONG OAK GROVE ROAD JUST SOUTH OF THE AIRPORT. (BMX)

1633 1 W NEELYS LANDING CAPE GIRARDEAU MO 3750 8952 FIRE DEPARTMENT REPORTS POSSIBLE BRIEF TORNADO TOUCHDOWN (PAH)

1724 3 NW DE SOTO JACKSON IL 3785 8927 EVENT TYPE … … … EF1 TORNADO EVENT DATE … … … FRIDAY MARCH 23 2012 EVENT TIME … … … BEGAN AT APPROXIMATELY 1224 PM CDT EVENT LOCATION … ..THE TORNADO BEGAN 3.5 NO (PAH)

1730 ELKVILLE JACKSON IL 3791 8924 PUBLIC REPORT RELAYED BY LAW ENFORCEMENT OF A TORNADO NEAR TRUAX AND TRAYER ROAD. (PAH)

1732 3 NW CARBONDALE JACKSON IL 3776 8926 JUST NORTH OF SIU CARBONDALE AIRPORT. BRIEF TOUCHDOWN AND IT WENT BACK UP. (PAH)

1742 2 E DU QUOIN PERRY IL 3800 8920 BRIEF ROPE TORNADO TOUCHDOWN AND GOLF BALL SIZE HAIL (PAH)

1749 14 SW DOTHAN GENEVA AL 3108 8556 911 CALL CENTER HAD REPORTS OF HOUSES WITH MINOR DAMAGE AND ROOFS DAMAGED AT/NEAR 1984 N COUNTY RD 49. TREES DOWN NEAR INTERSECTION OF COUNTY RD 73 AND SCOTT RD. (TAE)

1807 4 ENE HILLVIEW JEFFERSON KY 3809 8562 EF1 TORNADO TOUCHDOWN IN THE HERITAGE CREEK AREA. PATH LENGTH 2.5 MI … WIDTH 40 YD. LIFTED AT 212PM EDT (LMK)

1814 FERN CREEK JEFFERSON KY 3816 8560 TORNADO TOUCHDOWN IN THE HERITAGE CREEK AREA (LMK)

1826 OPDYKE JEFFERSON IL 3826 8879 (PAH)

1828 2 E FINCHVILLE SHELBY KY 3815 8529 EF1 TORNADO DAMAGED BARNS AND UPROOTED TREES ALONG 2.25 MILE PATH (LMK)

1857 2 SE CARTTER MARION IL 3852 8889 TORNADO BRIEFLY TOUCHED DOWN 2 MILES SOUTHEAST OF CARTER. (LSX)

1857 3 S IUKA MARION IL 3857 8879 TORNADO BRIEFLY TOUCHED DOWN 3 MILES SOUTH OF IUKA. (LSX)

1925 KOLOMOKI MOUNDS SP EARLY GA 3147 8493 LAW ENFORCEMENT REPORTED SEEING TORNADO ON THE GROUND. (TAE)

2039 2 NNW CENTER SQUARE SWITZERLAND IN 3886 8504 REPORT OF A BRIEF TORNADO TOUCHDOWN IN AN OPEN FIELD NORTH OF CENTER SQUARE. TORNADO THEN LIFTED AND THE FUNNEL CLOUD CONTINUED MOVING NORTHEAST. (ILN)

2330 5 WNW BLANCHESTER WARREN OH 3932 8407 A BRIEF TORNADO TOUCHED DOWN NEAR THE INTERSECTION OF HIGHWAYS 123 AND 132 IN HARLAN TOWNSHIP. (ILN)

2350 CLARKSVILLE CLINTON OH 3940 8398 A BRIEF TORNADO TOUCHED DOWN IN THE VILLAGE OF CLARKSVILLE. (ILN)

Detailed reports: SPC reports 12/03/23

A view from WV an VIS satellite, nicely visible a line of intense storms crossing S IN…

Yesterday, March 24th, the low was already moving towards Appalachian mountains and caused severe storms and locally lots oh hail in NC and VA. Here are the SPC reports:

Detailed reports: SPC reports 12/03/24

The WV satellite showing this low quite well, while notice the new upper trough approaching W US from the Pacific. It will be a focus for possible convective activity in the following days, especially over the N Plains.

As mentioned earlier, this rather slow moving intense upper low resulted in high rainfall amounts over parts of S CONUS, where drought over much of OK/TX is surely ended for some time. Some areas from E OK/E TX into LA/AR received between 6-15″ of rain, which is quite remarkable for just a couple of days period. Here is the last 14-days rainfall accumulation map from S US…

And another map of last 10-days accumulated rainfall from OK mesonet stations, notice the rainfall over the OK Panh as well where extreme drought was in place before. Indeed a nice soil moisture improvement for those areas with a good inch of rain reported.

Stay tuned!


Massive squall line with embedded strong tornadic supercells blasted through the Plains

As expected, a cold front was racing SE-wards across the Plains during the afternoon/evening hours and overnight bringing all types of severe weather all the way from western OK NE-wards into western IL. For now, here are only a couple of satellite/radar images and satelite animations as I am running out of time. More details about this impressive setup with be added in the next days.

It just had to be noted, that tornadic supercells with several late afternoon strong tornadoes caused extensive damage in NE-ern MO while some tornadoes also occured over SE KS and w-cntrl OK after dark. Unfortunatelly, also at least three people were killed and several people were injured by the strong tornado that swept through city of Kirksville, MO. Numerous chasers documented large wedge tornadoes in that area, some of them were pretty close calls.

Anyways, here is a SFC analysis at 21z when the cold front was extending from central IA SW-wards through NW-ern MO and SE-ern KS into NW-ern OK and further SW into TX Panhandle where dryline was extending SSW-wards into W TX.

SFC analysis 21z

Weakening capping inversion and strong SFC wind convergence along the frontal boundary soon initiated storms. Frontal boundary was clearly visible on satellites and radar images as can be seen on the next images, extending from Kansas City to just south of Wichita and towards Gage, OK.

VIS satellite 2133z

KS radar

Due to extreme instability and strong shear overlapping ahead of this boundary across warm sector, storms very rapidly organized into supercells, some of them soon became tornadic. Especially over northern MO as wind shear and helicity were very high. Numerous storms fired up along the front from IL towards W OK.

VIS satellite 2315z

OK radar

On this radar for whole MO state, a strong tornadic supercell with strong tornadoes that caused fatalities in Kirksville can be easily recognized.

MO radar

Given the strong forcing, very strong LL flow which tend to be parallel to the frontal boundary and weaker ML flow, supercell storms quickly went linear and several Q-linear mesoscale system started to form. As for around 00z, storms were already pretty linear which was clearly seen both on radar and satellites.

IR satellite 0015z

cntrl Plains radar 00z

Later on, a massive squall-line formed all the way from IL across MO into SE KS and W-CNTRL OK and blasting SE-wards across the Plains overnight, causing strong winds and hail damage. This WV satellite shows this impressive linear MCS on going at 0245z.

US WV satellite

A squall-line tend to be broken on its SW-ern flank and therefore a few discrete tornadic supercells were still ongoing near OKC and SW-wards towards Anadarko, which was damaged by a tornado and strong downbursts at late evening. Radar image shows this monster supercell in that area.

radar OK

Here are also few animations of IR, VIS and WV satellite images, showing the evolution of severe storms along thr cold front and clustering into a massive MCS later on.

  • VIS satellite: http://www.youtube.com/watch?v=VtK3dV7yT80
  • IR satellite: http://www.youtube.com/watch?v=FXTwgJDDwxA
  • WV satellite: http://www.youtube.com/watch?v=JT1l0WO-C50