Area Forecast Discussion
Issued by NWS Twin Cities, MN

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000
FXUS63 KMPX 101035
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
535 AM CDT THU APR 10 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CDT THU APR 10 2014

ONCE AGAIN...MAIN CONCERN IN THE SHORT TERM CENTERED AROUND FIRE
WEATHER/RED FLAG CONDITIONS. DID EXPAND THE RED FLAG ANOTHER ROW OF
COUNTIES...SEE THE FIRE WEATHER SECTION FOR MORE DETAILS ON THAT.

AT 3 AM...THE COLD FRONT ASSOCIATED WITH A SUB 980 MB SFC LOW SW OF
HUDSON BAY WAS JUST CLEARING THE ALBERT LEA/EAU CLAIRE AREAS. BEHIND
THIS FRONT...A LINE OF LIGHT SHOWERS/VIRGA WAS MOVING ACROSS THE
REGION ON THE LEADING EDGE OF THE H7 TROUGH. FARTHER WEST...SHORT
WAVE VISIBLE ON WATER VAPOR IMAGERY AND RAP H5 ANALYSIS OVER CENTRAL
BC WILL DROP SE ON NW FLOW INTO MN TONIGHT.

FIRST...THOSE SHOWERS THIS MORNING WILL CONTINUE TO PUSH EAST WITH
THE H7 TROUGH...THOUGH FOLLOWED THE IDEA OF THE HI-RES MODELS WITH
THESE SHOWERS BEING LARGELY OUT OF THE AREA BY 15Z AS SUBSIDENCE AND
DRYING IN THE WAKE OF THE FRONT HELP SPELL THE DEMISE OF THESE
SHOWERS. WILL HAVE CLOUDS TO WORK THROUGH THE AREA THIS MORNING LIKE
24 HOURS AGO...BUT BY THE AFTERNOON IT WILL BE PRETTY MUCH FULL
SUNSHINE FOR ALL UNTIL CLOUDS BEGIN TO INCREASE AHEAD OF THE
SHORTWAVE COMING OUT OF BC.

YESTERDAY...WE FOUND OURSELVES SQUARELY IN A WARM ADVECTIVE
PATTERN...WHICH LIMITED MIXING OF BOTH WINDS/DEWPOINTS. TODAY...WE
ARE ON THE OTHER SIDE OF THE FRONT...AND THOUGH THE COLD ADVECTION
WILL LARGELY BE DONE AFTER THIS MORNING...WE WILL STILL HAVE AN
ENVIRONMENT MUCH MORE CONDUCIVE TO MIXING IN ITS WAKE. OUR AIR FOR
THIS AFTERNOON COULD BE FOUND UP IN NE MONTANA/SRN SASKATCHEWAN
YESTERDAY...WHERE DEWPOINTS MIXED DOWN INTO THE MID TEENS. AS A
RESULT...BLENDED RAP DEWPOINTS /WHICH AGGRESSIVELY MIXES THEM
DOWNWARD TODAY/ INTO THE EXISTING FORECAST TO GET DEWPOINTS THIS
AFTERNOON DOWN INTO THE UPPER TEENS/LOWER 20S OUTSIDE OF AREAS WITH
WHAT IS A RAPIDLY DIMINISHING SNOWPACK. FOR HIGHS...WITH H85 TEMPS
SIMILAR TO WHAT WE SAW SUNDAY...WENT WITH HIGHS UP IN A SIMILAR AREA
IN THE UPPER 50S/LOWER 60S...OR ABOUT 5 DEGS ABOVE NORMAL. THOUGH 10
TO 20 DEGREES COOLER THAN YESTERDAY...THE 20 TO 25 DEG DROP IN DEWPS
ACTUALLY RESULTS IN HUMIDITIES BEING LOWER TODAY...WITH THE CURRENT
GRIDS DROPPING HUMIDITIES DOWN TO BETWEEN 20 AND 25 PERCENT FOR MUCH
OF THE AREA. WITH WINDS...FAVORED THEM TOWARD THE HIGHER END OF
GUIDANCE /IN THIS CASE THE NAM AND GFSLAMP/...AS MIXING IN THE POST
FRONTAL ENVIRONMENT SHOULD ALLOW US TO REACH OUR FULL POTENTIAL ON
WIND SPEEDS...WHICH IS RIGHT UP AROUND 20 MPH SUSTAINED.

TONIGHT...WHAT WE ARE CERTAIN ABOUT IS THAT CLOUD COVER WILL BE ON
THE INCREASE IN RESPONSE TO THE ARRIVAL OF THE BC WAVE. WHAT IS MUCH
LESS CERTAIN IS WHETHER OR NOT WE WILL SEE ANY PRECIP WITH IT. SREF
PROBS FOR MEASURABLE PRECIP ARE AT A MEAGER 40% /AS OPPOSED TO
60%-80% FOR WHATS MOVING THROUGH NOW/. BIG PROBLEM FOR SHOWERS
TONIGHT LOOKS TO BE THE SAME AS WHAT WE ARE SEEING NOW...VERY
DRY AIR BELOW 10K FT. WITH MODELS TRENDING DRIER...BROUGHT POPS DOWN
INTO THE 30S AND CONFINED CHANCE POPS TO CENTRAL MN...WHERE THE SREF
SPITS OUT WHAT LITTLE PRECIP IT HAS. LOOKS LIKE IT SHOULD BE SIMILAR
TO WHAT WE ARE SEEING EARLY THIS MORNING WITH MAINLY SPRINKLES/VIRGA.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 326 AM CDT THU APR 10 2014

NO MAJOR CHANGES TO THE LONG TERM FORECAST:

-STILL LOOKING AT A GOOD RAIN SIGNAL ON SATURDAY
-VERY HIGH CONFIDENCE IN PRONOUNCED COOL DOWN SUN-WED

THE WHOLE LONG WAVE PATTERN BECOMES MORE AMPLIFIED LATE THIS
WEEKEND AND THIS SETS THE STAGE FOR PRONOUNCED TEMPERATURE
PERTURBATIONS FROM NORMAL ACROSS THE CONUS. UNFORTUNATELY...THOSE
IN MN/WI IN FAVOR OF WARMER SPRING TEMPERATURES WILL HAVE TO WAIT
UNTIL AT LEAST LATE NEXT WEEK. ONCE THE BAROCLINIC ZONE DROPS SOUTH
OF THE AREA SATURDAY NIGHT WE SHOULD SEE TEMPS RUN 10 TO 20
DEGREES BELOW NORMAL FOR A FEW DAYS. THE AMPLIFICATION THAT OCCURS
IN THE EASTERN PACIFIC AND NORTH ATLANTIC IS IN THE FORM OF BUILDING
RIDGES WITH A DEEPENING TROUGH ACROSS THE CENTRAL CONUS.

BEFORE THE COLD AIR RETURNS ON SUNDAY...THERE ARE A COUPLE CHANCES
FOR RAIN WITH ISOLATED THUNDERSTORMS FRIDAY AND SATURDAY. A WEAK
SURFACE TROUGH DROPS ACROSS THE UPPER MISSISSIPPI RIVER VALLEY ON
FRIDAY WITH DIFFUSE FORCING...ESPECIALLY ACROSS SOUTHERN MN AND
WEST CENTRAL WI. THE 600-700MB FGEN LOOKS A LITTLE BETTER ACROSS
THE NORTHERN HALF OF THE STATE. WE ARE NOT VERY CONFIDENT IN
PRECIP ON FRIDAY AND HAVE KEPT POPS IN THE 15-30% RANGE. ON
SATURDAY...A NICE WEST-EAST ORIENTATED BAROCLINIC ZONE SETS UP
ACROSS MN/WI WITH STRENGTHENING S-SW FLOW AND MOISTURE ADVECTION
EARLY IN MORNING. AT THE SAME TIME...A SURFACE LOW DEEPENS AND
DROPS SOUTHEAST ALONG THE LEE SIDE OF THE ROCKIES IN THE CENTRAL
SOUTHERN PLAINS. THE BAROCLINIC ZONE DOESN`T MOVE VERY FAST AND
HANGS JUST TO OUT SOUTH SATURDAY NIGHT. THERE IS THE POTENTIAL FOR
COLD RAIN ON SUNDAY...ESPECIALLY IF YOU BUY THE 06Z NAM. BEST LI
NEAR AND MEAGER MUCAPE VALUES ALSO NOSE UP INTO MN ON SATURDAY
SUGGESTING AT LEAST WEAK EMBEDDED THUNDERSTORMS. SOUTHERN MN AND
PORTIONS OF WESTERN WI HAS THE POTENTIAL TO PICK UP SOME DECENT
RAINFALL THIS WEEKEND AS A RESULT OF THE SET UP.

EVENTUALLY THE SURFACE LOW IS EJECTED OUT OF THE SOUTHERN PLAINS
AND TRACKS MO/IL AS IT HEADS TOWARD THE GREAT LAKES. THIS SOLUTION
WOULD LEAVE US IN THE COLDER-DRIER SIDE OF THE SYSTEM...AND WE
WOULD MISS MOST OF THE PRECIP ON SUNDAY. DEPENDING ON CLOUD
COVER...HIGHS COULD STRUGGLE TO GET INTO THE 40S MON...TUE...AND
WED.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 522 AM CDT THU APR 10 2014

NOT A WHOLE LOT CHANGED WITH THE 12Z TAFS OTHER THAN TO BACK THE
WINDS TO A MORE WRLY DIR ACROSS CENTRAL MN TODAY. WILL AGAIN SEE
CLOUDY SKIES THIS MORNING GIVE WAY TO SUNNY SKIES TODAY...FOLLOWED
BY MORE MID/UPPER LEVEL CLOUDS RETURNING TONIGHT. HAVE KEPT ALL
TERMINALS DRY TONIGHT AS THIS UPPER WAVE LOOKS TO SUFFER FROM
THE SAME PROBLEM THIS PAST EVENINGS WAVE DID...DRY LOW LEVEL AIR.
CAN NOT RULE OUT SOME -SHRA TONIGHT...BUT NOT WORTH MENTIONING IN
TAFS AT THE MOMENT.

KMSP...VFR WILL RULE THIS TAF PERIOD...WITH WIND GUSTS PICKING
BACK UP WITH DAYTIME HEATING THIS MORNING. WILL HAVE A CHANCE FOR
SOME -SHRA BETWEEN 9Z AND 14Z...BUT DRY AIR WILL KEEP CONDITIONS
SIMILAR TO WHAT WE JUST HAD...6-10K FT CIGS WITH MAINLY VIRGA.

/OUTLOOK FOR KMSP/
FRI...VFR. WINDS WSW 5-10 KTS.
SAT...MVFR CIGS WITH SHRA LIKELY. CHANCE TSRA. WINDS S 10-15 KTS
      BCMG N 5-10 KT.
SUN...MAINLY VFR. CHC MVFR CIGS/SHRA. WINDS N 10-15 KT.

&&

.FIRE WEATHER...
ISSUED AT 326 AM CDT THU APR 10 2014

CONFIDENCE IN RED FLAG CONDITIONS BEING MET TODAY IS ACTUALLY HIGHER
THAN IT WAS 24 HOURS AGO FOR SEEING RED FLAG CONDITIONS YESTERDAY.
BEING IN A POST FRONTAL ENVIRONMENT WILL PROMOTE MORE EFFICIENT
MIXING AND DRIER HUMIDITIES. YESTERDAY WE HAD HUMIDITIES FORECAST TO
BE MORE OR LESS 24%-30% WHERE WE HAD THE RFW. FOR TODAY...HUMIDITIES
ARE FORECAST TO GET SOLIDLY DOWN INTO THE 20 TO 25 PERCENT RANGE FOR
ALL BUT THE NRN AND ERN FRINGES OF THE MPX AREA. THE BIG LIMITING
FACTOR FOR MEETING RED FLAG CONDITIONS FOR TODAY WILL BE GETTING
SUSTAINED WINDS OF 20 MPH. AGAIN THE MORE EFFICIENT MIXING SHOULD
MAKE THAT EASIER TO ACHIEVE AS WELL. WHEN ALL WAS SAID AND
DONE...HAD RED FLAG CONDITIONS FORECAST FOR NEARLY THE ENTIRE MN
PORTION OF THE MPX CWA. HOWEVER...HELD THE EXPANSION TO COUNTIES
WITHIN OUR WIND FAVORED REGIONS OF WRN/SRN MN WHERE HIGHS TODAY ARE
FORECAST TO GET INTO THE LOWER 60S.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...RED FLAG WARNING FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR
     MNZ047-048-054>058-064>067-073>076-082>085-091>093.

WI...NONE.
&&

$$

SHORT TERM...MPG
LONG TERM...CLF
AVIATION...MPG
FIRE WEATHER...MPG






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