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000
FXUS63 KDMX 280550
AFDDMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
1152 PM CST WED NOV 27 2013

.SHORT TERM /TONIGHT/...
ISSUED AT 322 PM CST WED NOV 27 2013

HIGH PRESSURE SLIDING OFF TO THE SOUTHEAST...WITH A WEAK SFC LOW
CURRENTLY CENTERED OVER CENTRAL SOUTH DAKOTA. WINDS EXPECTED TO BE
OUT OF THE SOUTH TO SOUTHEAST TONIGHT IN ADVANCE OF THE SFC LOW
APPROACHING THE CWA. SFC LOW ASSOCIATED WITH A WEAK UPPER LEVEL
IMPULSE DROPPING SOUTHEAST THROUGH THE REGION. SOME HIGH CLOUDS
ASSOCIATED WITH THIS SYSTEM TO STREAM THROUGH THE CWA...WITH ANY
PRECIPITATION EXPECTED TO STAY OFF TO THE NORTH/EAST WHERE DEEPER
MOISTURE IS LOCATED. WINDS TO SHIFT AROUND TO THE WEST/NORTHWEST
BEHIND ASSOCIATED COLD FRONT PUSHING INTO THE NORTHWESTERN HALF OF
THE CWA BY SUNRISE THURSDAY MORNING. THEREFORE TEMPS A LITTLE
TRICKY TONIGHT WITH THE INITIAL WAA THEN FOLLOWED BY CAA AND SOME
HIGH CLOUDS. KEPT THE TEMPS WARMER THAN READINGS FROM PREVIOUS
NIGHTS...AND SLIGHTLY WARMER THAN GUIDANCE BUT A BIT COOLER THAN
THE PREVIOUS FORECAST WITH MOST SITES DROPPING INTO THE TEENS
ACROSS THE CWA.

.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
ISSUED AT 322 PM CST WED NOV 27 2013

WEATHER WILL INITIALLY BE UNEVENTFUL WITH LITTLE CONCERN OUTSIDE
OF TEMPS. ANY FORCING ASSOCIATE WITH CURRENT MANITOBA SHORT
WAVE...JUST PRODUCING A GLANCING BLOW OF VIRGA TONIGHT...SHOULD
BE WELL N AND E OF IA BY THE BEGINNING OF THE PERIOD WITH
ATTENDANT SURFACE WAVE GETTING READY TO EXIT THE FORECAST AREA.
DRY AND INACTIVE NW FLOW WILL THEN BE IN PLACE WITH WEAK CYCLES OF
SEASONALLY COOL WARM AND COLD ADVECTION.

PATTERN WILL THEN BUCKLE HOWEVER WITH STRONG NW PACIFIC JET INTO WA.
HEIGHTS WILL BEGIN TO LOWER WITH INITIAL WEAK SHORT WAVE POSSIBLY
BRINGING SOME LIGHT PRECIP AS EARLY AS SUNDAY NIGHT OR
MONDAY...AND STARTING A MORE ACTIVE PERIOD INTO THE MIDDLE OF NEXT
WEEK. THERE IS LITTLE CONFIDENCE IN DETAILS HOWEVER AS THE GFS AND
ECMWF ARE SIMILAR TO THEIR RESPECTIVE ENSEMBLES AND DEPICTING
DIFFERENT SOLUTIONS. GFS/GEFS IS MORE ACTIVE WITH THE NRN STREAM
AND PUSHING SURFACE FRONT INTO IA WED WHILE THE ECMWF SUITE HAS A
MORE SLY EMPHASIS. THUS WILL BROAD BRUSH SAT-WED WITH LOW
POPS...GRADUALLY INCREASING HEADING INTO WED/DAY 7. TEMPS WILL
RETRUN TO MORE SEASONAL LEVELS...BUT BE HOVERING AROUND FREEZING
SO NOTHING BUT A RAIN/SNOW MIX WORDING UNTIL TIMING AND TEMP
PROFILE CONFIDENCE BOTH INCREASE.

&&

.AVIATION...28/06Z
ISSUED AT 1152 PM CST WED NOV 27 2013

A VERY WEAK UPPER LEVEL DISTURBANCE AND ASSOCIATED SURFACE LOW AND
COLD FRONT WILL SHIFT ACROSS THE AREA THROUGH THURSDAY.  GRADIENT
ACROSS THE STATE WILL INCREASE SLIGHTLY AFT 16Z WHICH WILL INCREASE
WINDS.  THERE IS A CAVEAT...SAT IS SHOWING LOW CIGS BEHIND THE FRONT
AND THIS MAY BRUSH KFOD AND KMCW OTHERWISE MAINLY PERIODS OF LOWER
VFR CIGS AS WIND FIELDS AT THE LEVEL OF THE STRATUS IS NEARLY DUE
NORTH.  SHOULD THE WIND GAIN A BIT MORE OF A WESTERLY COMPONENT FROM
THE PASSING UPPER WAVE THEN THE LOWER CIGS WOULD MOVE FURTHER INTO
IA.

&&

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

&&

$$

SHORT TERM...BEERENDS
LONG TERM...SMALL
AVIATION...FAB