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000
FXUS63 KDVN 082343
AFDDVN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
543 PM CST SAT MAR 8 2014

.SYNOPSIS...
ISSUED AT 325 PM CST SAT MAR 8 2014

WHILE TODAY REPRESENTS A COOL...MOSTLY CLOUDY...NORTH
WIND DOMINATED DAY ABOUT 10 DEGREES BELOW NORMAL...IS IS STILL MUCH
MORE MILD THAN THE PAST COUPLE WEEKS WEATHER. THUS...FOR SITES LIKE
MOLINE ILLINOIS...WE ARE EXPERIENCING THE 1ST 24 HOUR PERIOD ABOVE
FREEZING SINCE FEBRUARY 20TH.  HIGH PRESSURE IS LOCATED JUST
NORTHWEST...AND IS MOVING EAST.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 325 PM CST SAT MAR 8 2014

CLOUDS ARE THINNING FROM NORTH TO SOUTH...BUT DUE TO THE MARCH
SUN...SOME BANDS OF CUMULUS HAVE FORMED ON THE BACK EDGE. A SPRINKLE
OR FLURRY IS POSSIBLE IN THESE CONVECTIVE CLOUDS...BUT THEY ARE SO
FEW IN NUMBER...I WILL LEAVE THEM OUT OF THE FORECAST GRIDS TODAY.

TONIGHT WILL SEE A PERIOD OF CLEAR AND CALM CONDITIONS THIS EVENING
THROUGH EARLY MORNING...WITH GOOD RADIATIONAL COOLING. SNOW COVER IS
MORE OR LESS CONTINUOUS NORTH OF HIGHWAY 30...AND WILL KEEP THAT
AREA AT LEAST 8 DEGREES COOLER THAN FARTHER SOUTH. LOWER TO MID
TEENS OVER SNOW APPEARS LIKELY...WITH LOWER TO MID 20S FARTHER
SOUTH.

SUNDAY...WEST WINDS SHOULD DEVELOP...BECOMING SOUTHWEST. WITH MARCH
SUN...GOOD MIXING OVER INCREASINGLY SNOW FREE GROUND WE SHOULD BE
ABLE TO ACHIEVE OUR MAXIMUM POTENTIAL FROM OUR ATMOSPHERE. THUS...I
WILL GO A FEW DEGREES HIGHER THAN THE WARMEST GUIDANCE...NUMBERS
VERY CLOSE TO WHAT WE HAD AS THE GOING FORECAST. THIS AMOUNTS TO
HIGHS IN THE LOWER 40S NORTHEAST TO LOWER 50S SOUTH. MOST METRO
AREAS IN THE MIDDLE OF THIS RANGE WILL REACH 45 TO 47.

BY AFTERNOON...IT WILL BE RATHER BREEZY...SOUTHWEST SUSTAINED
AROUND 15 MPH...ESPECIALLY IN EASTERN IOWA.

ERVIN

.LONG TERM...(SUNDAY NIGHT THROUGH NEXT SATURDAY)
ISSUED AT 325 PM CST SAT MAR 8 2014

FORECAST FOCUS ON WARMER TEMPERATURES AND PCPN CHANCES TUESDAY-
WEDNESDAY MORNING.

SUNDAY NIGHT-MONDAY NIGHT...DRY CONDITIONS AND WELCOMED ABOVE NORMAL
TEMPS WILL BE SEEN AS A SURFACE LOW TRACKS WELL TO OUR NORTH ACROSS
THE GREAT LAKES. INCREASING LOW LEVEL WAA AND SOUTHWEST WINDS WILL
WILL KEEP HELP TEMPS ABOVE THE WARM SIDE OF GUIDANCE AND ABOVE
FREEZING SUNDAY NIGHT...DESPITE MOSTLY CLEAR SKIES. THE LAST TIME WE
HAD A DAY ENTIRELY ABOVE FREEZING IN THE QCA WAS BACK ON FEB 20TH.
MONDAY WILL BE A VERY PLEASANT DAY AS A LOW LEVEL THERMAL RIDGE WILL
BE OVERHEAD AND PROGGED 85H TEMPS AROUND 13C WILL ADVECT INTO THE
REGION. BUFKIT SOUNDINGS STILL SHOW AN INVERSION ALOFT ALTHOUGH A
LITTLE WEAKER...LIMITING THE MIXING DEPTH AND EXTENT OF WARMUP.
STILL...HIGHS ARE EXPECTED TO TOP OUT IN THE UPPER 40S ACROSS THE
FAR NORTH TO THE LOWER 60S IN THE SOUTH. IF MIXING DEPTH IS GREATER
IN FUTURE MODEL RUNS THEN HIGHS MAY STILL BE TOO LOW. THESE TWO
ABOVE NORMAL DAYS SHOULD ALLOW WHAT SNOW COVER IS LEFT TO RAPIDLY
MELT ESPECIALLY ACROSS OUR SOUTHERN TWO THIRDS OF THE CWA. AN
INCREASED RISK OF BREAK-UP ICE JAMS AND LOCALIZED FLOODING WILL ALSO
BE POSSIBLE ON AREA STREAMS AND RIVERS. THIS WILL CONTINUE TO BE
MONITORED IN FUTURE FORECASTS. INCREASING CLOUDS TO SPREAD OVER THE
AREA MONDAY NIGHT AHEAD OF NEXT SYSTEM TRACKING OUT OF THE ROCKIES.
MONDAY NIGHT LOWS SIMILAR TO SUNDAY NIGHT WITH READINGS IN THE LOW
TO MID 30S.

TUESDAY-WEDNESDAY...MODELS AGREE ON TRACKING A SHORTWAVE TROUGH
ACROSS THE ROCKIES INTO THE PLAINS DURING THE DAY TUESDAY. A SURFACE
LOW DEVELOPS ON THE LEE SIDE OF THE ROCKIES AND TRACKS ACROSS KANSAS
INTO SOUTHEAST MISSOURI AND SOUTHERN ILLINOIS BY 09Z WED. THERE STILL
REMAINS SIGNIFICANT TIMING/STRENGTH ISSUES WITH THE LATEST 12Z MODEL
SUITE. THE 12Z GFS/NAM IS A LITTLE FASTER WITH THE LOW TRACKING INTO
SOUTHERN ILLINOIS BY 06Z. THE ECMWF IS STRONGER AND SLOWER WITH THE
LOW REACHING SOUTHERN ILLINOIS IN THE 09Z-12Z TIME FRAME. MOST OF
PCPN WITH THIS SYSTEM WILL OCCUR POST FRONTAL AND THERMAL PROFILES
SUGGEST PCPN TO BEGIN AS RAIN TUE PM AND EVENTUALLY SWITCH OVER TO
ALL SNOW FROM NW TO SE BY WED AM. QPF AMOUNTS FOR THIS SYSTEM AT
THIS TIME WILL BE LESS THAN TWO TENTHS OF AN INCH AT ANY GIVEN LOCATION.
LATER FORECASTS WILL BE ABLE TO BETTER REFINE THESE AMOUNTS AS THE
EVENT DRAWS NEAR. SNOW AMOUNTS WILL BE MINIMAL AS THE SYSTEM EXITS
THE AREA.

THURSDAY-SATURDAY...UPPER AIR FLOW TO SWITCH BACK TO A SPLIT FLOW
PATTERN WITH MODELS ADVERTISING ANOTHER WARM UP FOR THE AREA. MOSTLY
SUNNY SKIES AND SOUTHERLY WINDS WILL PUSH TEMPS INTO THE LOW 40S TO
LOW 50S THURSDAY. A WEAK DRY COLD FRONT WILL MOVE THROUGH THE CWA
FRIDAY WITH ONLY A WIND SHIFT TO THE WEST NORTHWEST EXPECTED. HIGHS
FRIDAY TO BE EVEN WARMER REACHING THE UPPER 40S NORTH TO UPPER 50S
SOUTH. ANOTHER SHORTWAVE WILL DROP OUT OF CANADA SATURDAY BRINGING
ANOTHER CHANCE OF PCPN TO THE AREA.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 531 PM CST SAT MAR 8 2014

VFR WITH SOME PATCHY MVFR DECK OF STRATOCU CLOUDS CONTINUE TO SLOW
DIURNAL DEVELOPMENT AND PUSH SOUTHWARD...AND WITH ONGOING
SUBSIDENCE SHOULD MAKE FOR A CLEARING EVENING. LIGHT WEST TO
NORTHWEST WINDS OVERNIGHT UNDER PASSING SFC RIDGE...BECOMING
SOUTHWESTERLY BY SUNDAY MORNING. MAIN CONCERN INTERRUPTING AN
EXPECTED MAINLY VFR NIGHT IS THE POSSIBILITY OF FOG DEVELOPMENT IN
SOME LOCATIONS. BUT WILL BANK ON ENOUGH SFC WIND MOVEMENT TO
PREVENT ANY FOG LOWER THAN MVFR IF ANY FOG FORMS AT ALL. THE BRL
TERMINAL MAY HAVE A BETTER CHC FOR MVFR TO IFR FOG DEVELOPMENT
OVERNIGHT AND WILL HAVE TO WATCH TRENDS. SOUTHWEST WINDS
INCREASING TO 10-20KTS ON SUNDAY UNDER MAINLY CLEAR SKIES.  ..12..

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&

$$

SYNOPSIS...ERVIN
SHORT TERM...ERVIN
LONG TERM...GROSS
AVIATION...12