Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS63 KDVN 142301
AFDDVN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
601 PM CDT TUE APR 14 2015

.SYNOPSIS...
ISSUED AT 239 PM CDT TUE APR 14 2015

12Z UA ANALYSIS HAS AN 850MB HIGH OVER IOWA WITH AN 850MB FRONTAL
BOUNDARY FROM THE SOUTHERN PLAINS INTO THE OHIO VALLEY. SATELLITE
TRENDS THROUGH MID AFTERNOON SHOW PLENTY OF HIGH LEVEL CI/CS CLOUDS
ACROSS THE AREA.

18Z SFC ANALYSIS HAS THE HIGH FROM THE GREAT LAKES INTO THE SOUTHERN
PLAINS WITH A WEAK LOW IN THE TENNESSEE VALLEY. DEW POINTS WERE IN
THE 20S AND 30S FROM THE GREAT LAKES INTO THE PLAINS WITH 40S AND
HIGHER FROM THE OHIO VALLEY/SOUTHERN PLAINS ON SOUTH.

&&

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 239 PM CDT TUE APR 14 2015

QUIET AND DRY CONDITIONS WILL BE SEEN LATE THIS AFTERNOON THROUGH
MIDNIGHT AS HIGH PRESSURE SLOWLY MOVES INTO THE GREAT LAKES.

AFTER MIDNIGHT...SOME VERY WEAK FORCING WILL BEGIN MOVING INTO THE
FAR SOUTH. PROFILES OF THE ATMOSPHERE SHOW CONSIDERABLE DRY EASTERLY
FLOW ACROSS THE AREA. THUS SOME ISOLATED SPRINKLES AT BEST MIGHT
OCCUR IN THE EXTREME SOUTHWEST CORNER OF THE AREA AROUND SUNRISE.

WEDNESDAY...DRY CONDITIONS ARE EXPECTED FOR MUCH OF THE AREA AS DRY
EASTERLY FLOW CONTINUES. THE EXCEPTION WOULD BE THE FAR
SOUTHWEST/SOUTH AREAS WHERE SOME ISOLATED SPRINKLES MIGHT OCCUR
DURING THE MORNING. WEDNESDAY AFTERNOON SOME ISOLATED LIGHT SHOWERS
MAY BE POSSIBLE OVER THE FAR SOUTHWEST/WEST AREAS WITH A FEW
SPRINKLES POSSIBLE UP TO A WILLIAMSBURG IA TO MACOMB IL LINE.
HOWEVER...THE FORCING/MOISTURE CONTINUES TO REMAIN WEAK/LIMITED SO
THE POSSIBLY OF DRY CONDITIONS ACROSS THE ENTIRE AREA ARE THERE.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 239 PM CDT TUE APR 14 2015

MAIN FORECAST CONCERN IN THE LONG TERM IS THE SYSTEM THIS WEEK AND
INTO THE WEEKEND.  MODELS DIVERGE GREATLY ON THIS FORECAST MAKING
FOR A DIFFICULT FORECAST WITH LOW CONFIDENCE ON THE FINAL PRODUCT.
WE PROBABLY WILL SEE SOME PRECIP COME FROM FRIDAY THROUGH MONDAY
AFTERNOON...THE QUESTION IS WHEN AND HOW MUCH.

LETS START WITH THURSDAY. DRY EASTERLY WINDS WILL FIGHT AN ADVANCING
WAVE WITH S FLOW INTO THE AREA.  THE FORCING IS RATHER MEAGER.
MODELS SUGGEST THAT CONVECTION WILL BE ONGOING ACROSS THE GULF
STATES.  THIS SIGNAL ALONG WITH MODEL SOUNDINGS...SUGGESTS THAT
THERE WILL BE LITTLE TO NO PRECIP OVERNIGHT WEDNESDAY AND INTO
THURSDAY AM.  HAVE GONE WITH SCHC ACROSS THE SOUTH AND SPRINKLES
ELSEWHERE ACROSS THE AREA.

FRIDAY...MODELS ARE HAVING A HARD TIME WITH THE SENSIBLE WEATHER
FIELDS.  MODEL DIAGNOSTICS REVIEW SUGGESTS A FEW THINGS.  FIRST THE
GFS IS DEEPER THAN THE GEFS MEAN AND OTHER MODELS AND SEEMS TO HAVE
LESS RUN TO RUN CONSISTENCY IN THIS PERIOD.  THE GEFS MEMBERS...WITH
THE EXCEPTION OF 4 DO NOT HAVE THIS DEEP WAVE.  THE ECMWF..GEM AND
09Z SREF ARE IN AGREEMENT WITH THE CLOSED H5 LOW PLACEMENT ON
FRIDAY.  WPC AND MY ANALYSIS SUGGESTS THAT THE GFS IS AN OUTLIER.
THE ONLY WAY THE GFS IS CORRECT IS IF THE WAVE TO THE NORTH IS AS
STRONG AS THE GFS FORECASTS AND MAKES THE TROUGH MORE PROGRESSIVE.
AT THIS TIME THAT THE ENERGY IS STILL OFF SHORE...SO THE FORECAST
COULD BECOME CLOSER TO WHAT THE GFS HAS.  AS SUCH ONLY WENT WITH THE
SCHC OF POPS ON FRIDAY...WHEN THE GFS SUGGESTS WIDESPREAD QPF ACROSS
THE AREA.  THIS FRIDAY FORECAST HAS A HIGH POSSIBILITY OF A BUST
DEPENDING ON WHICH SOLUTION IS CORRECT.

AFTER THIS THE WEEKEND APPEARS TO BE WET WITH INCONSISTENCY IN THE
MODEL SOLUTIONS REMAINING.  I THINK WE WILL SEE RAIN...JUST NOT SURE
WHEN YET.  SINCE THE SUPERBLEND IS AN AVERAGE OF THE MODELS IT
SUGGESTS THAT WE HAVE RAIN THE ENTIRE PERIOD.  AT THIS TIME BOTH
MODELS SUGGEST THAT THE RAIN WE HAVE WILL BE MORE
PROGRESSIVE...SUGGESTING THAT THE CURRENT FORECAST OF PRECIP FOR 3
DAYS WILL LIKELY LAST HALF A DAY TO A ONE FULL DAY DEPENDING ON
WHICH SOLUTION IS CORRECT.  IF YOU WANT A NICE WEEKEND ROOT FOR THE
GFS...IF YOU WANT A RAINY WEEKEND...THE ECMWF IS YOUR MODEL.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 557 PM CDT TUE APR 14 2015

OVERCAST HIGH CLOUDS WILL CONTINUE...ALONG WITH EAST WINDS BETWEEN
5 AND 10 KTS THROUGH THE NEXT 24 HOURS. LOW PRESSURE WILL APPROACH
FROM THE SOUTH WEDNESDAY...BUT WITH VERY DRY AIR IN PLACE OVER
IOWA AND ILLINOIS...THIS SHOULD MAINLY PRODUCE MID AND HIGH CLOUDS
ABOVE 12000 FT.
ERVIN

&&

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

$$

SYNOPSIS...08
SHORT TERM...08
LONG TERM...GIBBS
AVIATION...ERVIN






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.