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000
FXUS63 KDMX 111150
AFDDMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
550 AM CST WED DEC 11 2013

...UPDATED AVIATION DISCUSSION...

.SHORT TERM /TODAY/...
ISSUED AT 358 AM CST WED DEC 11 2013

WINDS AND TEMPS WERE THE MAIN FORECAST CONCERN TODAY. SHARP
PRESSURE GRADIENT AND A DECENT PV ANOMALY WILL CONTINUE TO CAUSE
GUSTY WINDS THROUGH MUCH OF THE MORNING. WINDS ATOP THE MIXED LAYER
GO FROM AROUND 30 KNOTS THROUGH 12Z BEFORE DIMINISH PAST 15Z AS THE
SURFACE HIGH BUILDS INTO THE STATE. THE SNOW RECEIVED TUESDAY NIGHT
SHOULD BE LIGHT ENOUGH TO CAUSE SOME BLOWING SNOW THROUGH THE
MORNING HOURS AND FELT CONFIDENT ENOUGH TO KEEP THE ADVISORY GOING
THROUGH 15Z TO HANDLE THE VISIBILITY ISSUES AS WELL AS THE COLD WIND
CHILL VALUES. LEANED TOWARD THE SLIGHTLY WARMER NAM GUIDANCE FOR
TEMPERATURES TODAY AS WE SHOULD SEE TEMPS DROP THROUGH THE MORNING
WITH THE STRONG CAA BUT SLIGHTLY REBOUND THIS AFTERNOON WITH SUNNY
SKIES AND LIGHTER WINDS SHIFTING WESTERLY.

.LONG TERM /TONIGHT THROUGH TUESDAY/...
ISSUED AT 358 AM CST WED DEC 11 2013

TODAYS SYSTEM WILL BE PULLING OUT OF THE AREA BY THIS EVENING WITH
WARM ADVECTION RETURNING DURING THE OVERNIGHT. THE PRIMARY CONCERN
EARLY THIS EVENING IS THE POTENTIAL FOR A QUICK DROP IN
TEMPERATURES DUE TO THE NEW SNOW SIMILAR TO WHAT OCCURRED MONDAY
EVENING. EXPECT THIS SCENARIO WILL OCCUR OVER THE NORTHEAST WHERE
THE WARM ADVECTION WILL BE DELAYED. SOME MID LEVEL CLOUDS SHOULD
ACCOMPANY THE WARM ADVECTION ALOFT THEREFORE TIMING OF THE SFC
WARM ADVECTION AND ANY CLOUDS WILL BE KEY. A FEW LOCATIONS MAY DIP
TO 10 BELOW IN THE WATERLOO AND WAVERLY AREAS BEFORE THE WARM
ADVECTION ARRIVES. WIND CHILL VALUES MAY REACH 20 TO 25 BELOW FOR
A PERIOD OVER THE NORTHEAST THIS EVENING AND MAY REQUIRE AN
ADVISORY. THE SOUTHWEST FLOW WILL CONTINUE INTO THURSDAY WITH 850
MB TEMPERATURES RISING ABOVE 0C. THIS WARM NOSE WILL EXTEND DOWN
TO AROUND 925 MB WHERE A LARGE INVERSION WILL SET UP. IT WILL BE
DIFFICULT TO WARM TOO MUCH OVER THE SNOW PACK THEREFORE HIGHS WILL
BE LIMITED TO THE 20S.

A COUPLE OF SYSTEMS WILL INFLUENCE THE WEATHER FOR THE END OF THE
WEEK IN TO THE WEEKEND. THE CLOSED LOW TO THE SOUTHWEST OF THE
CALIFORNIA COAST WILL EJECT EAST AND BECOME ENGULFED BY THE
SOUTHERN STEAM THURSDAY INTO FRIDAY. THIS SYSTEM WILL LIFT
MOISTURE NORTH TOWARD SOUTHEAST IOWA BY FRIDAY AND WILL BRING THE
CHANCE FOR A WINTRY MIX TO THAT AREA. DURING THIS TIME...A SYSTEM
WILL BE DROPPING THROUGH THE NORTHWEST FLOW AND WILL PUSH A COLD
FRONT THROUGH THE STATE AND WILL END PRECIPITATION CHANCES TO THE
SOUTH AS DRIER AIR ARRIVES. A MORE SIGNIFICANT SYSTEM WILL DROP
SOUTHEAST THROUGH THE NORTHERN PLAINS AND GREAT LAKES REGION SATURDAY
AND SATURDAY NIGHT. THIS SYSTEM MAY BRING LIGHT SNOW BACK TO THE
STATE. IN ADDITION IT WILL BRING THE NEXT SURGE OF COLD AIR TO THE
REGION. GENERAL TRENDS SUGGEST IT WILL BE MORE OF A GLANCING BLOW
WITH THE COLDEST SURGE REMAINING TO THE NORTHEAST.

&&

.AVIATION...11/12Z
ISSUED AT 548 AM CST WED DEC 11 2013

CAA WILL CONTINUE THIS MORNING WITH A BRIEF BAND OF MVFR CIGS TO
AFFECT OTM AND DSM. OTHERWISE...EXPECTING WINDS TO CALM DOWN LATER
THIS MORNING AS SURFACE RIDGE MOVES INTO THE STATE. VFR PREVAIL
THROUGH TONIGHT.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR BLACK
HAWK-BOONE-BREMER-BUTLER-CALHOUN-CERRO GORDO-EMMET-FRANKLIN-
GRUNDY-HAMILTON-HANCOCK-HARDIN-HUMBOLDT-JASPER-KOSSUTH-MARSHALL-
PALO ALTO-POCAHONTAS-POWESHIEK-SAC-STORY-TAMA-WEBSTER-WINNEBAGO-
WORTH-WRIGHT.

&&

$$

SHORT TERM...PODRAZIK
LONG TERM...DONAVON
AVIATION...PODRAZIK