Area Forecast Discussion
Issued by NWS Des Moines, IA

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000
FXUS63 KDMX 110501
AFDDMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
1201 AM CDT FRI APR 11 2014

.SHORT TERM /TONIGHT/...
ISSUED AT 305 PM CDT THU APR 10 2014

A QUIET NIGHT IS IN STORE ACROSS THE AREA IN WAKE OF THIS MORNINGS
COOL FRONT. MODERATE NORTH NORTHWEST BREEZES THIS AFTERNOON WILL
DIMINISH RAPIDLY IN THE EVENING AS A SURFACE HIGH PRESSURE AREA
MOVES IN FROM THE WEST. THIS HIGH PRESSURE AREA WILL SLIDE ACROSS
SOUTHERN IOWA OVERNIGHT WITH WINDS GOING LIGHT AND VARIABLE...THEN
COMING AROUND TO SOUTH SOUTHWEST BY FRIDAY MORNING. THIS WILL LEAD
TO MOSTLY CLEAR SKIES WITH ONLY A FEW HIGH CLOUDS. THERE IS SOME
POTENTIAL FOR LIGHT SHOWERS ACROSS NORTHERN IOWA ON FRIDAY
MORNING...BUT THESE CHANCES WILL PRIMARILY BE AFTER 12Z THUS WILL
NOT BE DISCUSSED FURTHER IN THE TONIGHT SECTION.

.LONG TERM /FRIDAY THROUGH THURSDAY/...
ISSUED AT 305 PM CDT THU APR 10 2014

MORE ACTIVE WEATHER INTO THROUGH THE WEEKEND...THOUGH FOCUS NOW
TURNS TO WET...POTENTIAL STORMS AND BREEZY WEATHER RATHER THAN
DRY AND BREEZY. MODELS CONSISTENT IN BRINGING IN NEXT UPSTREAM
WAVE ACROSS THE NORTHERN PLAINS TOMORROW...INCREASING WARM AIR
ADVECTION OVER IOWA AND SURROUNDING STATES THROUGH THE DAY. WITH A
WEAK BOUNDARY AND SOME LIFT ACROSS NORTHERN SECTIONS EARLY
FRIDAY...ANY PRECIP THAT OCCURS WILL BE LIMITED TO THE FAR NORTH
ONCE AGAIN. OVERALL WARMING EXPECTED AS FRONT LIFTS NORTHEAST AND
WARM AIR ADVECTION SPREADS ACROSS THE STATE. TEMPS RECOVER NICELY
DURING THE AFTERNOON AS H850 TEMPS INCREASE AGAIN TO 7C TO 10C
FROM EAST TO WEST. CURRENT MODEL DEW POINT FORECASTS LOOK TOO HIGH
IN THE SHORT TERM AND HAVE TRIMMED FORECAST VALUES THROUGH 00Z FRI
NIGHT. HOWEVER...EVEN WITH DRIER DEW POINTS AND WARMER
TEMPS...FIRE DANGER FRIDAY SHOULD REMAIN IN CHECK AS WINDS WILL
NOT BE TOO STRONG FOR THE DAY. MOISTURE WILL CONTINUE TO INCREASE
FRIDAY NIGHT AND SATURDAY AS H850 FLOW INCREASES AND TROUGH
APPROACHES FROM THE WEST. AS ELEVATED INSTABILITY RETURNS EARLY
SATURDAY...CHANCES FOR THUNDER INCREASE OVER THE NORTH WHERE
FRONTAL FOCUS IS BEST...AND THEN THE SOUTH AS THE DAY PROGRESSES.
MODELS GENERALLY NOW IN BETTER AGREEMENT ON THE EVOLUTION OF THE
WEEKEND SYSTEM. TEMPS WILL WARM NICELY SOUTH ON SATURDAY WHICH
WILL ALLOW FOR GREATER INSTABILITY IN THE AFTERNOON AND EVENING
HOURS. WITH THE BOUNDARY SITUATED OVER CENTRAL IOWA BY LATE
AFTERNOON...BEST CHANCES FOR ANY SEVERE WEATHER WOULD BE FROM MID
TO LATE AFTERNOON THROUGH EARLY EVENING WITH LIKELIHOOD THAT
ACTIVITY WOULD THEN BE ELEVATED THROUGH THE NIGHT. FORECAST 0-6KM
BULK SHEAR VALUES SUGGEST 25 TO 40KTS BOTH SATURDAY MORNING NORTH
AND AGAIN IN THE MID TO LATE AFTERNOON SOUTH THROUGH THE OVERNIGHT
HOURS. THIS SHOULD BE ENOUGH TO FAVOR SOME ORGANIZATION AND
POTENTIAL ROTATION IF WE WARM ENOUGH BY LATE DAY. WITH BOUNDARY
MOVING SOUTH DURING THE AFTERNOON HOURS...FOCUS WILL MOSTLY BE
RIGHT ALONG THE BOUNDARY FOR WIND AND HAIL. WARM AND HUMID
WEATHER WILL BE IN PLACE ACROSS CENTRAL/SOUTH WITH HIGHS IN THE
70S AND DEW POINTS IN THE LOWER TO MID 50S. AS THE FRONT DRIFTS
SOUTH SAT NIGHT...NORTH WINDS WILL TAKE OVER AND DIMINISH THE SEVERE
THREAT. THE 12Z GFS IS BEGINNING TO COME AROUND THE THE PREVIOUS
EURO SOLUTIONS OF KEEPING MUCH OF THE AREA WET THROUGH SUNDAY WITH
RAIN AND SCT THUNDER. HAVE INCREASED POP A BIT JUST INTO DEF
CATEGORY FOR SUNDAY WITH CONTINUATION INTO SUNDAY NIGHT PRIOR TO
ENDING BY MONDAY MORNING. EXPECTED RAINFALL AMOUNTS MAY STILL
REACH THE HALF INCH TO SPOTTY 2 INCH RANGE ACROSS THE AREA. STILL
A CHANCE FOR BRIEF MIX/CHANGEOVER AS THE SYSTEM PULLS OUT SUNDAY
NIGHT...THOUGH NOT EXPECTING ANY ACCUMULATION AT THIS TIME.

&&

.AVIATION...11/06Z
ISSUED AT 1158 PM CDT THU APR 10 2014

HIGH PRESSURE OVER IA WILL MOVE EAST WITH FLOW BECOMING SWLY. WEAK LOW
OVER SD WILL MOVE EAST WITH ASSOCIATED TROUGH DROPPING INTO IA FRI
AFTERNOON WITH NO SIGNIFICANT WEATHER. WARM FRONT WILL DEVELOP
ACROSS IA FRI NIGHT WITH MID LEVEL CLOUDS FORMING.

OUTLOOK...WARM FRONT WILL LIFT NORTH OF IA BY SAT MORNING.
ISOLATED SHOWERS ARE POSSIBLE LATE FRI NIGHT...BUT CONDITIONS WILL
REMAIN VFR. DETERIORATING CONDITIONS LATE SAT INTO SUN WITH
WIDESPREAD RAIN AND THUNDERSTORMS DEVELOPING.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...LEE
LONG TERM...REV
AVIATION...MS APR 14



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