Area Forecast Discussion
Issued by NWS Twin Cities, MN

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
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 200910
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
410 AM CDT MON APR 20 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 318 AM CDT MON APR 20 2015

SFC ANALYSIS SHOWS A 984MB LOW PRES CENTER OVER
NRN MI WITH A TRAILING N-S CDFNT FROM THE OH RIVER VALLEY THRU THE
LWR MISS RIVER VALLEY. A COUPLE OF SFC TROFS ARE VAGUELY EVIDENT ON
WV SATELLITE IMAGERY ALONG WITH SFC MAP ANALYSIS OVER NRN MN AND WRN
WI ROTATING AROUND THE SFC LOW. ALOFT...A DEEP LONGWAVE TROF WITH A
CUTOFF LOW WITHIN IT WILL DRIVE SEWD INTO THE N-CENTRAL CONUS WITH
THE UPR LOW CENTERING ITSELF OVER THE CENTRAL GREAT LAKES BY TUE
MRNG. THE POINT OF EMPHASIS WITH THESE FEATURES ARE...STRONG WINDS
DUE TO A TIGHT PRES GRADIENT IN THE WAKE OF THE SURFACE FRONTAL
SYSTEM AND THE POTENTIAL FOR -SHRA THIS AFTN UNDERNEATH THE PASSING
UPR LVL LOW. FIRST...WITH RESPECT TO THE WINDS...WINDS WILL BE FROM
THE NORTHWEST THROUGHOUT THIS SHORT-TERM PORTION OF THE FCST.
HOWEVER....H925-H850 WINDS WILL RUN CONTINUALLY 30 KT ALL DAY...AND
WITH MODEST SUBSIDENCE ALONG WITH THE TIGHT PRES GRADIENT...SFC
SUSTAINED WINDS WILL EASILY HIT 20-25KT /ALONG WITH GUSTS UPWARDS OF
35-40KT/ FOR MUCH OF CENTRAL-SRN MN TDA...PARTICULARLY LATE THIS
MRNG INTO THE EARLY EVE HRS. THEREFORE...HAVE OPTED TO HOIST A WIND
ADVY FOR MUCH OF CENTRAL-SRN MN. THE SECOND POINT WILL BE ISOLD-SCT
RAIN SHOWERS THIS AFTN THRU THIS EVE AS THE UPR LOW MOVES ACRS.
STEEP LOW-MID LVL LAPSE RATES MAY WELL BE EFFICIENT ENOUGH TO
PRODUCE SLEET/GRAUPEL UNDER ANY STRONGER CELLS WITH THE COLD CORE
LOW ALOFT. AS THE UPR LVL LOW SETTLES INTO WI TNGT...CONTINUED CAA
WILL DROP LOWS TO THE FREEZING MARK FOR NRN AND ERN PORTIONS OF THE
CWFA. WITH CHCS FOR ISOLD-SCTD PRECIP CONTINUING OVERNIGHT THRU TUE
MRNG...THERE IS A SMALL CHANCE FOR SOME OF THE SHOWERS TO MIX WITH
AND CHANGE OVER TO -SN BY DAYBREAK. IF ANYTHING...A COUPLE TENTHS OF
SNOW ACCUMULATION MAY BE POSSIBLE ON GRASSY AREAS NORTH OF THE I-94
CORRIDOR. REGARDING TEMPS...A MUCH COOLER DAY IS ON TAP WITH
WIDESPREAD STRATUS COVER AND CAA CONTINUING UNDER NW FLOW ALOFT.
HIGHS TDA WILL ONLY HIT THE MID-UPR 40S WITH LOWS TNGT DROPPING TO
THE LOW 30S.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 318 AM CDT MON APR 20 2015

LITTLE CHANGE TO THE LONG TERM FORECAST. THE MAIN CONCERN
CONTINUES TO BE THE UPPER LOW THAT WILL SLOWLY DRIFT FROM ITS
CURRENT POSITION JUST NORTH OF MINNESOTA...TO THE NORTHERN GREAT
LAKES FOR MUCH OF THE MID WEEK TIME FRAME. BEYOND THAT...THE
MODEL GUIDANCE CONTINUES TO HAVE TROUBLE AGREEING.

BY TUESDAY MORNING...OUR AREA WILL BE ENCOMPASSED BY WRAP-AROUND
MOISTURE AND CYCLONIC CIRCULATION FROM THE UPPER LOW. DIURNALLY
DRIVEN SHOWERS CONTINUE TO LOOK LIKE A GOOD BET...SO WENT AHEAD
AND INCREASED POPS INTO THE LIKELY CATEGORY FOR TUESDAY AFTERNOON
IN WESTERN WI. IT STILL APPEARS SNOW SHOWERS WILL BE POSSIBLE
EARLY TUESDAY MORNING BEFORE SURFACE TEMPERATURES CAN WARM INTO
THE 40S. IT IS POSSIBLE FOR A DUSTING TO A FEW TENTHS TO
ACCUMULATE ON GRASSY SURFACES...MAINLY ACROSS WEST CENTRAL WI.
MEANWHILE...A SURFACE LOW IN EASTERN ONTARIO WILL DEEPEN AND
APPROACH 990MB...WHILE HIGH PRESSURE PUSHES SOUTH OUT OF MANITOBA.
THIS WILL KEEP THAT STRONG PRESSURE GRADIENT ACROSS THE REGION AND
STRONG NORTHWEST WINDS WILL CONTINUE...BUT EXPECT THEM TO BE JUST
A FEW MPH WEAKER THAN THE WINDS WE`LL SEE TODAY.

SKIES WILL CLEAR FOR MUCH OF SOUTHERN MN BY WEDNESDAY...WHILE WEST
CENTRAL WI REMAINS TRAPPED UNDER MOISTURE ASSOCIATED WITH THE
QUASI-STATIONARY UPPER LOW TO THE EAST. IT WILL BE YET ANOTHER
WINDY DAY ON WEDNESDAY WITH THE SURFACE HIGH PUSHING SLIGHTLY
FURTHER SOUTH AND THE AFOREMENTIONED LOW REMAINING STUBBORNLY IN
PLACE.

FOR THURSDAY AND BEYOND...THE GFS IS STILL INDICATING THE UPPER
LOW WILL STRETCH BACK WEST THROUGH MUCH OF THE PERIOD...WHILE THE
EC CONTINUES TO HOLD FIRM IN SHOVING THE UPPER LOW TO THE EAST
AND AS AN UPPER RIDGE TRIES TO BUILD IN. THE EC HAS SHOWN TO BE
MORE CONSISTENT IN THE DP/DT SO I LEAN A LITTLE MORE TOWARDS ITS
SOLUTION...WHICH WOULD INDICATE DRY WEATHER FOR THE WEEKEND...BUT
HIGH TEMEPRATURES STILL LOOK TO BE SLIGHTLY COOLER THAN NORMAL.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1255 AM CDT MON APR 20 2015

POTENT CDFNT HAS PUSHED THRU THE REGION EARLIER ON SUNDAY WITH
MAINLY MVFR AND LOW VFR CLOUDS IN ITS WAKE. A SWATH OF PERSISTENT
-RA REMAINS OVER FAR WRN WI...MAINLY AFFECTING KRNH BUT IS
EXPECTED TO SHIFT EAST AND NIP KEAU BEFORE DAYBREAK. AFTER THE
PRECIP CLEARS OUT...STRATUS WILL REMAIN IN PLACE FOR MUCH OF THE
DAY. ANOTHER ROUND OF -SHRA IS POSSIBLE THIS AFTN AS AN UPR LVL
DISTURBANCE SWOOPS IN FROM THE NW BEHIND THE DEPARTING CDFNT...BUT
NO VSBY RESTRICTIONS ARE EXPECTED. CONDS WILL IMPROVE LATE THIS
AFTN INTO THIS EVE TO VFR BUT MID-UPR LVL CIGS ARE LIKELY TO
REMAIN. STRONG NW WINDS WILL BE THE RULE THIS ENTIRE TAF...
INCLUDING WINDS HITTING AND EXCEEDING THE 20G30KT MARK FOR MUCH OF
THE DAY.

KMSP...WINDS WILL REMAIN IN THE 300-320 RANGE ALL DAY WITH
CEILINGS EXPECTED TO REMAIN ABOVE 1700FT. ANY PRECIP RECEIVED AT
KMSP IS NOT EXPECTED TO DROP VSBY BELOW 6SM ALTHOUGH STRATUS
CLOUDS WILL REMAIN IN PLACE ALL DAY.

/OUTLOOK FOR KMSP/
TUE...VFR. WINDS NW AT 20G30KTS.
WED...VFR. WINDS NW AT 15G25KTS.
THU...VFR. WINDS NW 10-15KT.

&&

.FIRE WEATHER...
ISSUED AT 318 AM CDT MON APR 20 2015

WITH TEMPERTURES REMAINING QUITE COOL TODAY...RH VALUES WILL
STRUGGLE TO DIP BELOW 40 PERCENT. VERY STORNG NORTHWEST WINDS ARE
STILL EXPECTED...WITH GENERALLY 20-30 MPH SUSTAINED WINDS WITH
GUSTS OF 35-45 MPH. SHOWERS ARE POSSIBLE ACROSS THE AREA THIS
AFTERNOON. THE MORE CONCERNING DAY LOOKS TO BE TOMORROW...AS
WESTERN MN WILL DRY OUT FURTHER AND HEAT UP MORE THAN TODAY. WIND
SPEEDS WILL BE SLIGHTLY LESS THAN TODAY...BUT NOT BY MUCH SO IT
WILL STILL BE BREEZY. RH VALUES COULD APPOACH 30 PERCENT IN
WESTERN MN...BUT EVEN LOWER IF MORE ABUNDANT SUNSHINE BREAKS OUT
AND HEATS THE SURFACE MORE THAN CURRENTLY EXPECTED.
STILL...TERMPERATURES WILL BE COOL...WITH HIGHS IN THE UPPER 40S
AND LOW 50S EXPECTED IN WESTERN MN TOMORROW...AND GENERALLY MID
40S FURTHER EAST.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND ADVISORY FROM 11 AM THIS MORNING TO 7 PM CDT THIS EVENING
     FOR MNZ041>043-047>051-054>070-073>077-082>085-091>093.

WI...NONE.
&&

$$

SHORT TERM...JPC
LONG TERM...SPD
AVIATION...JPC
FIRE WEATHER...SPD


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