Area Forecast Discussion
Issued by NWS Twin Cities, MN

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS63 KMPX 211201
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
701 AM CDT MON JUL 21 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 356 AM CDT MON JUL 21 2014

PESKY BKN-OVC SC CONTINUES OVER EASTERN MN AND WEST CENTRAL WI EARLY
THIS MORNING. THERE WAS BEEN A DECREASE IN THE CLOUDINESS ON THE
WESTERN FLANK AS LOW LEVEL TROUGHING ACROSS WESTERN MN TRANSITIONS
INTO LOW LEVEL RIDGING. THIS RIDGE AXIS IS PROGGED INTO WESTERN WI
BY EARLY THIS AFTERNOON. THIS SHOULD AID IN SUNSHINE BECOMING MORE
DOMINATE ACROSS EASTERN AREAS OF THE FA THROUGH THE MORNING. LOW
LEVEL THERMAL PROGS REMAIN CONSISTENT FOR HIGHS TODAY REACHING
AROUND 90 IN WEST CENTRAL WI WITH LOWER 90S ACROSS CENTRAL AND
SOUTHERN MN. MIX-DOWN STILL SHOWS POTENTIAL FOR MID 90S IN WEST
CENTRAL MN AND THIS REMAINS WHERE THE WARMEST HIGHS ARE FORECAST. A
PLUME OF LOWER 70 DEW POINTS EXTENDS NORTHWARD THROUGH THE CENTRAL
PLAINS EARLY THIS MORNING WITH AN EXTENSION INTO WESTERN AND CENTRAL
AREAS OF MN. CONFIDENCE REMAINS HIGH THAT DEW POINTS WILL RISE INTO
THE LOWER 70S ACROSS THE EASTERN FA WITH MIDDLE TO UPPER 70S IN THE
WESTERN FA. THIS COUPLED WITH HIGHS AROUND 90 TO THE LOWER 90S
RESULTS IN APPARENT TEMPERATURES FROM 100 TO 110 DEGREES ACROSS
CENTRAL AND SOUTHERN MN AND BORDERING AREAS OF WEST CENTRAL WI. THE
HIGH END APPARENT TEMPERATURES ARE IN THE UPPER END OF THE MINNESOTA
RIVER VALLEY WHERE DEW POINTS APPROACH 80 DEGREES THIS AFTERNOON.
THE EXCESSIVE HEAT WARNING FOR THE TWIN CITIES METRO AND THE HEAT
ADVISORY FOR THE REST OF CENTRAL AND SOUTHERN MN REMAIN IN EFFECT
THROUGH THIS EVENING.

THE STORM PREDICTION CENTER SHIFTED THE MODERATE RISK AREA THAT
COVERED MUCH OF OUR CWA FOR TODAY AND TONIGHT BODILY NORTHWESTWARD
OVERNIGHT. VARIOUS WRF SOLUTIONS ARE SHOWING SEVERE CONVECTION
ERUPTING OVER EASTERN ND LATE THIS AFTERNOON WITH A COMPLEX OF
STORMS RACING EASTWARD ACROSS PRIMARILY THE NORTHERN THIRD MN EARLY
TONIGHT. THE SOUTHERN EXTENT OF THE STORMS BRUSH OUR CENTRAL MN
COUNTIES WHICH IS NEAR A STRONG MID LEVEL CAP. THE PRIMARY SEVERE
WEATHER THREAT FOR US IS DAMAGING STRAIGHT LINE WINDS WITH SPEEDS
FROM 60 TO 80 MPH. CONFIDENCE IN THE WRF FORECASTS IS SUPPORTED BY
THE FORWARD PROPAGATION MBE VELOCITY FROM THE NAM FOR KSTC WHERE IS
SHOWS 260 DEGREES AT 59 KNOTS. HENCE...THIS RESULTED IN A LOWERING
OF THE POP FORECAST ACROSS SOUTHERN MN AND ADJOINING AREAS OF WEST
CENTRAL WI TONIGHT WITH LIKELY TO CATEGORICAL POPS CONFINED TO
CENTRAL MN AND POINTS EASTWARD. THIS ALSO RAISES THE POSSIBILITY
THAT IF THE STORMS STAY NORTH OF THE TWIN CITIES METRO TONIGHT...
THEN THE LOW TEMPERATURE IN THE HEART OF THE TWIN CITIES WILL LIKELY
BE NEAR 80 DEGREES. THIS WOULD NECESSITATE THAT THE EXCESSIVE HEAT
WARNING WOULD NEED TO BE EXTENDED THROUGH THE NIGHT FOR HENNEPIN AND
RAMSEY COUNTIES.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 356 AM CDT MON JUL 21 2014

THE SEVERE MCS SHOULD BE EAST OF THE CWA BY THE BEGINNING OF THE
PERIOD. A DRY COLD FRONT WILL BE PUSHING THROUGH AROUND MIDDAY.
THERMAL RIDGING WILL BE LOCATED ACROSS SRN MN AND WRN WI EARLY
TUESDAY MORNING BUT WILL BE SAGGING SOUTH WITH THE FRONT THROUGH
THE DAY SO THE HIGH TEMP FORECAST WILL BE TRICKY. IT WILL START
OFF VERY WARM WITH TEMPS POSSIBLY NEAR 80 SO IT WOULDN/T TAKE MUCH
TO WARM BACK TO NEAR 90 ACROSS THE SOUTHERN AREAS BEFORE THE
FRONT. DEW POINTS WILL DROP...SO THAT MAY ALLOW FOR TEMPS TO REACH
THEIR FULL POTENTIAL AS WELL. RAISED TEMPS A BIT FOR THE SOUTHERN
AND EASTERN AREAS WITH THE THOUGHT THAT THE PRECISE TIMING OF THE
FRONT WILL HAVE THE FINAL SAY.

HIGH PRESSURE WILL BUILD IN TUESDAY NIGHT AND REMAIN NEARBY
THROUGH THURSDAY. MUCH LOWER HUMIDITY...CLEAR SKIES AND SLIGHTLY
BELOW NORMAL TEMPS CAN BE EXPECTED.

A WARM FRONT ASSOCIATED WITH THE BUILDING RIDGE OVER THE ROCKIES
WILL BRING THE NEXT CHANCE OF RAIN LATE WEEK. THE SETUP IS LESS
THAN FAVORABLE FOR WIDESPREAD SOAKING RAIN SO KEPT POPS IN THE
CHANCE RANGE.

THE GFS AND ECMWF ARE SINGING A SLIGHTLY DIFFERENT TUNE FOR THE
WEEKEND. INSTEAD OF A CUT OFF LOW DROPPING SOUTHEAST INTO THE
GREAT LAKES...A BROAD NORTHWEST FLOW WILL CONTINUE WITH BELOW
NORMAL TEMPS. THIS WOULD ALLOW FOR A DRIER SCENARIO THAN HAS BEEN
ADVERTISED. INTERESTINGLY...BEYOND THE CURRENT FORECAST PERIOD
BOTH MODELS DO RETROGRADE SAID FEATURE WESTWARD WITH EVEN COOLER
TEMPS FOR NEXT WEEK. AFTER THE WARM UP FOR THE NEXT COUPLE
DAYS...IT DOES NOT APPEAR THE HEAT WILL RETURN FOR QUITE SOME
TIME.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 701 AM CDT MON JUL 21 2014

AN EXTENSIVE AREA OF BKN-OVC035-050 EXISTS THIS MORNING ALONG AND
EAST OF A LINE FROM KSTC TO KAEL. THE WEST EDGE OF THIS CLOUD
SHIELD HAD BEEN ADVANCING FAIRLY QUICKLY TO THE EAST IN THE 06Z-
10Z TIME FRAME...BUT HAS SINCE COME TO NEARLY A HALT. THE
CLOUDINESS SEEMS TIED TO LOW LEVEL TROUGHING JUST TO THE WEST
ALONG WITH PERSISTENT LOW LEVEL THETA-E ADVECTION. THE RUC
CONTINUES TO SHOW THAT THE LOW LEVEL TROUGHING WILL BECOME RIDGING
THIS MORNING WITH THE RH AROUND 850MB DIMINISHING SIGNIFICANTLY.
UNTIL THIS OCCURS...SITES FROM KSTC ON EAST AND SOUTH MAY HAVE A
TEMPORARY DROP TO BKN-OVC028-030. THERE WILL ALSO BE SOME 4-6SM BR/HZ
THIS MORNING...PRIMARILY FROM KRWF ON NORTHWARD THROUGH KAXN. ON
THE CONVECTIVE FRONT...SOME SMALL STORMS WILL PASS NORTH OF KAXN
AND KSTC THROUGH THE MORNING. DURING THE VERY LATE AFTERNOON AND
EARLY EVENING...STRONG TO SEVERE STORMS WILL ERUPT OVER EASTERN
NORTH DAKOTA AND SPREAD QUICKLY EASTWARD ACROSS NORTHERN MN. WHILE
THIS IS OCCURRING THERE ARE INDICATIONS THAT OTHER AREAS OF
CONVECTION MAY DEVELOP NORTH OF KBRD AND WELL AS EAST OF KABR.
THE FIRST TAF SITE AT RISK FOR THE STORMS AND STRONG WINDS IS
KAXN. CONFIDENCE IS HIGH ON WIND WITH THE STORMS SO 30G45KTS WAS
INCLUDED IN THE 02Z-05Z PERIOD. THESE STORMS MAY BOW ESE INTO KSTC
IN THE 03Z-06Z PERIOD AND REACH KRNH BY 06Z. CONFIDENCE IS NOT
HIGH ON A SIGNIFICANT WIND EVENT FOR KMSP WITH MOST CONVECTION
ALLOWING MODELS KEEPING THE ACTIVITY ACROSS THE NORTHERN 1/3RD OF
MN AND WI. A COLD FRONT WILL BE FOLLOWING LATE IN THE NIGHT.
THERE ARE INDICATIONS THAT STRATUS WITH CIGS UNDER 1K MAY FORM
ALONG AND BEHIND THE FRONT ACROSS CENTRAL AND WEST CENTRAL MN DUE
TO THE SUPER MOIST LOW LEVEL ATMOSPHERE AS DEW POINTS TODAY CLIMB
INTO THE MIDDLE AND UPPER 70S. CONFIDENCE IS NOT HIGH ON THIS WITH
MVFR BR INCLUDED LATE TONIGHT ALONG WITH SCT010.

KMSP...VFR CEILINGS (040) DISSIPATING THIS MORNING WITH INCREASING
MID/HIGH LEVEL CLOUDS THIS AFTERNOON. SOME CONVECTION MAY PASS THE
AIRFIELD IN THE 06Z-10Z PERIOD BUT CONFIDENCE IS NOT HIGH WITH
MUCH BETTER CHANCES TO THE NORTH. SE WINDS 6-10 KNOTS THIS MORNING
AND 10-12 KNOTS THIS AFTERNOON AND TONIGHT.

/OUTLOOK FOR KMSP/
TUE...VFR. WINDS NW 10-15KTS.
WED...VFR. WINDS NE AT 10KTS.
THU...VFR. WINDS SE AT 10KTS.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...HEAT ADVISORY FROM 11 AM THIS MORNING TO 9 PM CDT THIS EVENING
     FOR MNZ041>045-047>059-064>067-073>078-082>085-091>093.

     EXCESSIVE HEAT WARNING FROM 11 AM THIS MORNING TO 9 PM CDT THIS
     EVENING FOR MNZ060>063-068>070.

WI...HEAT ADVISORY FROM 11 AM THIS MORNING TO 9 PM CDT THIS EVENING
     FOR WIZ014-023-024.

&&

$$

SHORT TERM...RAH
LONG TERM...BORGHOFF
AVIATION...RAH







USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.