A tight pressure gradient around strong low pressure tracking across southern Canada produced gusty southwest winds over southern Wisconsin during the day on March 10th. The surface gradient winds were enhanced by a 40-knot low level jet that mixed down to the surface during maximum daytime heating.
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The episode as NWS MKX wrote it up.
A tight pressure gradient around strong low pressure tracking across southern Canada produced gusty southwest winds over southern Wisconsin during the day on March 10th. The surface gradient winds were enhanced by a 40-knot low level jet that mixed down to the surface during maximum daytime heating. Sustained wind speeds were between 30 mph and 35 mph (26 to 30 knots), with gusts of 40 to 47 mph (35 to 41 knots). There were scattered reports of snapped power-lines due to the impact of fallen tree branches.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Milwaukee, WI wrote its last area forecast discussion before the first event at Mar 10, 11:56 AM CST, 1 hour 34 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 1156 AM CST SAT MAR 10 2012 .UPDATE...WIND ADVISORY ISSUED THIS MORNING FOR NORTHEAST COUNTIES...AS LATEST SOUNDINGS SHOWING UP TO 45 MPH IN THE TOP HALF OF THE MIXING LAYER. GFS AND RUC SOUNDS ARE PARTICULARLY AGGRESSIVE...SUGGESTING GUSTS TO NEARLY 50 MPH POSSIBLE THIS AFTERNOON. HAVE ALREADY SEEN GUSTS AS HIGH AS 43 MPH AT FOND DU LAC...SO APPEARS THAT THINGS ARE ON THEIR WAY. WINDS WILL EVENTUALLY EASE LATE THIS AFTERNOON AND INTO THE EVENING AS DAYTIME MIXING IS LOST. WITH RELATIVELY CALM UPPER LEVEL FLOW AND ONLY A FEW CIRRUS IN SIGHT ON SATELLITE IMAGERY...SKIES EXPECTED TO REMAIN NEARLY CLOUD FREE THIS AFTERNOON. TEMPERATURES FORECAST BY PREVIOUS SHIFT HAVE BEEN GOOD THROUGH THE MORNING. 925MB TEMPS OF 5 TO 8 C AND NEAR ADIABATIC LAPSE RATES SUGGEST HIGHS TODAY IN THE UPPER 50S IN THE WEST AND LOWER 50S EAST. SHORT TERM GUIDANCE IS WARMER THAN THIS BY A COUPLE OF DEGREES. HOWEVER...GIVEN WAA PATTERN IN SOUTHWEST FLOW...THINK PREVIOUS FORECAST OF LOW 60S IN THE WEST AND MID-UPPER 50S IN THE EAST WAS ONLY SLIGHTLY OVERDONE...SO BUMPED TEMPS DOWN A COUPLE OF DEGREES. && .AVIATION/18Z TAFS/...WINDY AFTERNOON IN STORE FOR SOUTHERN WISCONSIN...AS WINDS CONTINUE TO INCREASE UNDER TIGHT PRESSURE GRADIENT. SFC WINDS WILL BACK OFF LATE AFTERNOON AND EVENING AS DAYTIME MIXING IS LOST...OPENING THE DOOR AGAIN FOR WIND SHEAR. DECIDED TO KEEP THE WIND SHEAR IN THE TAFS THROUGH THE NIGHT AS 45 KT WINDS EXPECTED AT ABOUT 2 KFT. OTHERWISE...MOSTLY CLEAR SKIES TO CONTINUE INTO SUNDAY MORNING. MID AND HIGH LEVEL CLOUDS WILL INCREASE TOMORROW AFTERNOON AS LOW PRESSURE DRAWS NEAR...WITH RAIN AND LOWER CLOUDS MOVING IN DURING THE EVENING HOURS. && .PREV DISCUSSION... /ISSUED 342 AM CST SAT MAR 10 2012/ TODAY AND TONIGHT...FORECAST CONFIDENCE HIGH. STRONG LOW PRESSURE WILL CONTINUE EWD ACROSS CANADA WITH A 50 TO 60KT SWLY LOW LEVEL JET SHIFTING EWD FROM THE UPPER MS RIVER VALLEY INTO THE GREAT LAKES. STRONG WARM ADVECTION WILL OCCUR WITH 925 MB TEMPS AND FORECAST TRAJECTORIES YIELDING MAX TEMPS AROUND 60F. GUSTY WINDS TO 35 TO 40 MPH WHICH IS UNDER WIND ADVISORY CRITERIA. PRESSURE GRADIENT TO DECREASE BY TNT BUT STILL ENOUGH OF A PRESSURE GRADIENT INCLUDING A 40 KT LLJ TO KEEP WINDS GOING AND THUS RELATIVELY MILD LOW TEMPS. A VERY DRY AIRMASS WILL SUPPORT MO SUNNY DAY AND A CLEAR NIGHT. SHORT TERM...SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM TO HIGH. SUNDAY APPEARS TO BE A DRY DAY...AS SHORT TERM MODELS SUGGEST ANY APPRECIABLE UPWARD VERTICAL MOTION WITH APPROACHING UPPER LOW SHOULD REMAIN SOUTHWEST OF THE AREA. THUS...EXPECT JUST INCREASING CLOUDS DURING THE DAY SUNDAY. 925MB TEMPERATURES SUPPORT HIGHS IN THE LOWER 60S AWAY FROM LAKE MICHIGAN...WITH GOOD LOW LEVEL MIXING. WINDS SHOULD TURN ONSHORE LATE IN THE DAY CLOSE TO SHORE...KEEPING HIGHS THERE SOMEWHAT COOLER. UPPER LOW SHIFTS FROM THE CENTRAL PLAINS TO EAST CENTRAL MINNESOTA SUNDAY NIGHT...THEN OPENS UP AS IS IT SHIFTS NORTHEAST THROUGH LAKE SUPERIOR MONDAY. AREA FORECAST SOUNDINGS CONTINUE TO SATURATE DURING THIS TIME...WITH ROBUST UPWARD VERTICAL MOTION. MAY SEE A LULL IN THE RAIN MONDAY MORNING WITH DRY SLOT...BUT SHOULD SEE MORE DEVELOPMENT IN THE AFTERNOON WITH INFLUENCE OF PASSING VORTICITY MAXIMUM. CONTINUED TO GO WITH HIGH POPS SUNDAY NIGHT INTO MONDAY...TAPERING OFF AS MONDAY WEARS ON. WEAK HIGH PRESSURE THEN SLIDES INTO THE REGION MONDAY NIGHT...GRADUALLY ENDING THE RAIN. TEMPERATURES WILL REMAIN ON THE MILD SIDE DURING THIS TIME. LONG TERM...TUESDAY THROUGH FRIDAY...FORECAST CONFIDENCE MEDIUM TO HIGH. WARM AIR ADVECTION KICKS IN AGAIN ACROSS THE REGION TUESDAY INTO WEDNESDAY...WITH 925MB TEMPERATURES JUMPING INTO THE LOWER TO MID TEENS CELSIUS RANGE. GOOD LOW LEVEL MIXING AND SOME SUNSHINE SHOULD ALLOW FOR HIGHS TO JUMP INTO THE 60S AWAY FROM THE LAKE TUESDAY...THEN INTO THE 70S ACROSS THE AREA WEDNESDAY WITH SOUTHWEST WINDS. COLD FRONT THEN SHIFTS SOUTHEAST THROUGH THE AREA LATE WEDNESDAY AND WEDNESDAY NIGHT. AREA FORECAST SOUNDINGS FROM THE GFS SHOWING SOME MEAN LAYER CAPES AND MOISTURE DURING THIS TIME...SO CONTINUED TO MENTION THUNDER IN FORECAST. TEMPERATURES WILL REMAIN MILD AFTER FRONTAL PASSAGE THROUGH THE REST OF THE WEEK. AVIATION/12Z TAFS/...A 50-60 KT LLJ WILL DEVELOP OVER THE REGION TODAY WITH LOW LEVEL WIND SHEAR POSSIBLE OVER SOUTH CENTRAL WI THIS AM BEFORE WINDS AND MIXING INCREASE THERE. LOW LEVEL WIND SHEAR IS THEN MARGINAL FOR TNT AS THE PRESSURE GRADIENT DECREASES AND MIXING CEASES WITH A 40 KT LLJ REMAINING OVER THE AREA. OTHERWISE VFR CONDITIONS WILL PREVAIL TODAY THROUGH SUNDAY. MARINE...A GALE WARNING IS IN EFFECT FROM 6 AM UNTIL 6 PM. A STRONG SWLY 50-60KT LOW LEVEL JET WILL SHIFT FROM THE UPPER MS RIVER VALLEY INTO THE GREAT LAKES TODAY IN RESPONSE TO STRONG LOW PRESSURE MOVING EWD ACROSS CANADA. THE PRESSURE GRADIENT AND STRONG LOW LEVEL JET WILL PRODUCE WINDY CONDITIONS OVER THE LAKE INCLUDING WIND GUSTS TO GALE FORCE. HIGH WAVES WILL OCCUR ESPECIALLY NORTH OF NORTH POINT LIGHTHOUSE. THE GUSTY WINDS AND HIGH WAVES WILL LINGER INTO THE EVENING SO A SMALL CRAFT ADVISORY MAY NEED TO FOLLOW THE CURRENT GALE WARNING. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ051-052-058>060. LM...GALE WARNING UNTIL 6 PM CST THIS EVENING FOR LMZ643>646. && UPDATE...WIMBERLEY/DDV TODAY/TONIGHT AND AVIATION/MARINE...GEHRING SUNDAY THROUGH FRIDAY...WOOD
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 920 AM CST SAT MAR 10 2012 WIZ046-047-051-052-056>060-062>072-111115- MARQUETTE-GREEN LAKE-FOND DU LAC-SHEBOYGAN-SAUK-COLUMBIA-DODGE- WASHINGTON-OZAUKEE-IOWA-DANE-JEFFERSON-WAUKESHA-MILWAUKEE- LAFAYETTE-GREEN-ROCK-WALWORTH-RACINE-KENOSHA- 920 AM CST SAT MAR 10 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL WISCONSIN...SOUTH CENTRAL WISCONSIN AND SOUTHEAST WISCONSIN. .DAY ONE...TODAY AND TONIGHT A WIND ADVISORY IS IN EFFECT TODAY FOR FOND DU LAC...SHEBOYGAN... DODGE...WASHINGTON AND OZAUKEE COUNTIES. EXPECT SOUTH WINDS OF 25 TO 30 MPH WITH GUSTS TO 45 MPH. HIGH PROFILE VEHICLES ON EAST TO WEST ORIENTED ROADS WILL BE MOST AFFECTED BY THE SOUTHERLY WIND. SOUTH WINDS ELSEWHERE ACROSS THE AREA WILL ALSO BE QUITE STRONG...BUT REMAINING JUST BELOW WIND ADVISORY CRITERIA. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY THERE IS A SLIGHT CHANCE FOR THUNDERSTORMS NEXT WEDNESDAY AND WEDNESDAY NIGHT AS A WEAK COLD FRONT CROSSES SOUTHERN WISCONSIN. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED IN THE NEXT SEVEN DAYS. LMZ643>646-111115- SHEBOYGAN TO PORT WASHINGTON WI- PORT WASHINGTON TO NORTH POINT LIGHT WI- NORTH POINT LIGHT TO WIND POINT WI- WIND POINT WI TO WINTHROP HARBOR IL- 920 AM CST SAT MAR 10 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF LAKE MICHIGAN. .DAY ONE...TODAY AND TONIGHT A GALE WARNING IS IN EFFECT UNTIL 6 PM THIS EVENING DUE TO INCREASING SOUTH TO SOUTHWEST WINDS BETWEEN HIGH PRESSURE TO THE SOUTHEAST AND LOW PRESSURE MOVING EAST ACROSS CANADA. HIGH WAVES WILL DEVELOP ESPECIALLY NORTH OF NORTH POINT LIGHTHOUSE. THE BREEZY WINDS AND HIGH WAVES WILL LIKELY LINGER INTO THIS EVENING SO A SMALL CRAFT ADVISORY MAY NEED TO FOLLOW THE CURRENT GALE WARNING. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY THERE IS A SLIGHT CHANCE FOR THUNDERSTORMS NEXT WEDNESDAY AND WEDNESDAY NIGHT AS A WEAK COLD FRONT CROSSES SOUTHERN WISCONSIN. WWW.WEATHER.GOV/MKX DAVIS
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1230 PM CST SAT MAR 10 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0800 AM HIGH SUST WINDS SHEBOYGAN 43.75N 87.72W
03/10/2012 M42.00 MPH SHEBOYGAN WI C-MAN STATION
SGNW3. GUSTS TO 47 MPH.
&&
WIMBERLEYPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
101 PM CST SAT MAR 10 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1253 PM HIGH SUST WINDS FOND DU LAC AIRPORT 43.77N 88.49W
03/10/2012 M30 MPH FOND DU LAC WI ASOS
KFLD 21026G34KT
&&
WIMBERLEYThe national radar mosaic for the moment the first event began.
8 strong wind. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2012Every state in 2012This day in weather historyWarnings in Wisconsin, March 2012
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 371530, 371531, 371532, 371533, 371534, 371535, 371537, 371538.