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 191115
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
515 AM CST WED NOV 19 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CST WED NOV 19 2014

SHORT TERM CONCERNS INCLUDE TIMING OF SNOW EXITING TO THE EAST THIS
MORNING AND BLOWING SNOW THREAT TODAY.  THEN EXTENT OF CLEARING
OVERNIGHT AND LOW TEMPERATURE POTENTIAL.

WATER VAPOR SATELLITE IMAGERY SHOWING DECENT SHORT WAVE MOVING
ACROSS SOUTHERN MN THIS MORNING.  SURFACE ANALYSIS HAS THE COLD
FRONT PUSHING INTO CENTRAL MN AT 08Z.  THIS FRONT IS PROGGED TO EXIT
INTO WISCONSIN AFTER 12Z.  THE LIGHT SNOW OVER AHEAD OF THE FRONT
SHOULD MOVE INTO WESTERN WISCONSIN THROUGH 12Z AS WELL.  THIS MAY
LINGER THROUGH ABOUT MID MORNING THERE.  HIGH SLR SNOWFALL OVER THE
AREA...HAS YIELDED AROUND 1/2 TO 1 INCH OF FLUFFY SNOW.  THOUGHT NOW
IS THAT THIS WAS MAINLY INTO CENTRAL AND EASTERN MN OVERNIGHT.  THE
STRONGEST WINDS ARE FORECAST TO REMAIN OVER WESTERN INTO SOUTH
CENTRAL MN.  THE GREATEST PRESSURE RISES ARE NOW DROPPING ACROSS
SOUTHWEST MN INTO NORTHWEST IOWA.  THIS SHOULD PROHIBIT SIGNIFICANT
GUST POTENTIAL INTO SOUTHERN MN.  STRONG CAA AND TIGHTENING
PRESSURE GRADIENT WILL STILL GENERATE GUSTS TO AT LEAST 35 MPH INTO
THE DAY.  BLOWING SNOW COULD BECOME A GREATER THREAT IF WINDS BECOME
STRONGER THAN ALREADY FORECAST. WILL HAVE TO MONITOR CONDITIONS INTO
THE MORNING FOR POSSIBLE ADVISORY.

CLOUDS AND FLURRIES WILL REMAIN OVER THE CWA OR MUCH OF THE DAY.  WE
COULD SEE SOME EROSION IN THE CLOUDS TO THE SOUTHWEST...BUT MOSTLY
CLOUDY CONDITIONS ARE ANTICIPATED WITH CAA AND WEAK CYCLONIC FLOW TO
THE EAST.  TEMPERATURES WILL PROBABLY SETTLE OUT AROUND 20 DEGREES FOR
HIGHS OVER MUCH OF THE CWA TODAY.

MODELS SUGGEST LOW LEVEL HUMIDITY TO REMAIN HIGH OVER THE EASTERN
HALF OF THE CWA INTO TONIGHT.  THE SURFACE RIDGE DROPS SOUTHEAST
ACROSS EASTERN SOUTH DAKOTA AND IOWA TONIGHT INTO THURSDAY...SO
WILL TREND CLOUDIER CONDITIONS TO THE EAST.  LOWS TONIGHT WILL BE
DIFFICULT TO FORECAST WITH UNCERTAINTY IN CLOUD COVER.  WILL FOLLOW
MORE OF AN ALL BLEND APPROACH TO TEMPERATURES FOR NOW.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 400 AM CST WED NOV 19 2014

LONG TERM FORECAST CONCENTRATIONS ARE CENTERED AROUND CHANCES FOR
FREEZING PRECIPITATION OVER THE WEEKEND...AND THEN ON A
POTENTIALLY IMPACTFUL WINTER SYSTEM FOR MONDAY.

THE PERIOD STARTS OUT ON A FAIRLY BENIGN NOTE ON THURSDAY...WITH
SURFACE HIGH PRESSURE IN CONTROL. IT WILL BE ANOTHER CHILLY DAY
HOWEVER...WITH 925 MB TEMPS AROUND -14C AND WEAK COLD AIR
ADVECTION CONTRIBUTING TO HIGHS IN THE LOW/MID TEENS. CLEAR SKIES
AND THE CONTINUED INFLUENCE OF SFC HIGH PRESSURE WILL LIKELY YIELD
SUBZERO TEMPS ACROSS MUCH OF THE FORECAST AREA ON THURSDAY
NIGHT...WITH POSSIBLY ONLY A FEW LOCATIONS IN WEST AND SOUTH
CENTRAL MN HOLDING A COUPLE DEGREES ON THE POSITIVE SIDE OF ZERO.

FRIDAY BRINGS THE RETURN TO SOUTHERLY FLOW AS SURFACE HIGH
PRESSURE SLIDES EAST/SOUTHEAST OF THE AREA AND TROUGHING BEGINS TO
APPROACH FROM THE WEST/SOUTHWEST. WEAK WARM AIR ADVECTION DEVELOPS
AHEAD OF AN ADVANCING TROUGH. BOTH 19.00Z GFS AND ECMWF MODELS
CAME IN SLOWER...DRIER AND FARTHER EAST FOR FRIDAY NIGHT...AND
THEREFORE MEASURABLE PRECIP CHANCES WERE REMOVED UNTIL AFTER
DAYBREAK SATURDAY. CHANCES ON SATURDAY INTO SATURDAY NIGHT LOOK TO
BE CONFINED TO AREAS EAST OF THE INTERSTATE 35 CORRIDOR /PRIMARILY
WI/. SURFACE TEMPS SHOULD BE PRIMARILY ABOVE 32 DEGREES THROUGH
MOST OF SATURDAY AND SATURDAY NIGHT GIVEN THE LOW LEVEL WARM AIR
ADVECTION AND CLOUD COVER...SO THE FREEZING RAIN THREAT APPEARS
LIMITED THROUGH THEN. REGARDING HIGH TEMPS...THE WEEKEND WILL BE A
WELCOMED RETURN FOR MANY TO NEAR NORMAL HIGHS IN THE 30S.

ON SUNDAY...THE TROUGH LIFTS TO SOUTHERN LAKE MICHIGAN...AND
DEEPENS TO CIRCA 985 MB. FREEZING/MIXED PRECIPITATION CONCERNS THEN
INCREASE FOR SUNDAY...ALTHOUGH THERE IS A DECENT CHANCE THAT WE
COULD BE DRY SLOTTED FOR MUCH OF THE DAY.

SUNDAY NIGHT AND MONDAY REALLY LOOKS TO BE THE TIME PERIOD OF
UTMOST CONCERN...GIVEN BOTH GFS AND ECMWF MODELS CRANK NORTHWEST
WINDS UP TO 25-35 MPH /SUSTAINED/ IN CONJUNCTION WITH DEFORMATION
SNOW TAKING PLACE AS THE AFOREMENTIONED LOW DEEPENS FURTHER AND
PIVOTS NORTH-NORTHWEST TO LAKE SUPERIOR. WILL DEFINITELY NEED TO
MONITOR FOR THE BLOWING SNOW POTENTIAL...WITH NOTABLE SNOW ACCUMS
ALSO A POSSIBILITY. HOWEVER...MODELS HAVE LACKED RUN TO RUN
CONSISTENCY WITH THEIR HANDLING OF THE KEY PLAYER...THE STRENGTH
OF THE NORTHERN STREAM SHORTWAVE...SO HAVE KEPT SNOW CHANCES IN
THE LOW CHANCE CATEGORY AT THIS POINT.

BY TUESDAY...WEATHER CONDITIONS SHOW IMPROVEMENT...WITH MODELS
INDICATING SURFACE HIGH PRESSURE BUILDING IN.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 505 AM CST WED NOV 19 2014

MAINLY MVFR CIGS/VSBYS IN SNOW OVER WEST CENTRAL WI EARLY THIS
MORNING...AHEAD OF COLD FRONT. THIS SHOULD WANE IN A FEW
HOURS...WITH FLURRIES POSSIBLE ACROSS MOST OF THE AREA THROUGH THE
DAY. DRIER AIR WORKS INTO WESTERN AREAS DURING THE AFTERNOON.
EXPECT ANY MVFR CIGS BECOMING VFR WITH SCATTERING OUT OF CLOUDS
INTO THE EVENING AS SURFACE HIGH BUILDS EAST OVER THE EASTERN
DAKOTAS INTO SOUTHWEST MN. STRONG W-NW WINDS BEHIND FRONT WITH
SOME GUSTS OVER 30 KTS POSSIBLE. BEST PRESSURE RISES DROP INTO
IOWA THIS MORNING BUT GRADIENT REMAINS TIGHT ENOUGH TO GENERATE
STRONG WINDS ALONG WITH THE POTENTIAL FOR SOME BLOWING SNOW.

KMSP...FLURRIES REMAIN INTO THE MORNING WITH AS COLD FRONT DEPARTS
AND WINDS INCREASE. SHOULD SEE SOME MVFR CIGS INTO THE AFTERNOON
PER TREND OF THE SREF PROBS. THEN SCATTERING OUT INTO THE
EVENING. WILL KEEP THE STRONG WINDS GUSTS 25-30KTS POSSIBLE THROUGH
THE DAY. SHOULD SLACKEN OFF IN THE EVENING BECOMING LIGHT WEST LATE
TONIGHT.

/OUTLOOK FOR KMSP/
THU AFTN...VFR. WINDS WNW 10 KTS.
FRI...VFR. WINDS SSE 10-15 KTS.
SAT...VFR. CHC MVFR CIGS. WINDS SSW 10 KTS.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

$$

SHORT TERM...DWE
LONG TERM...LS
AVIATION...DWE





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