Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

Home | Current Version | Previous Version | Graphics & Text | 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

632
FXUS63 KDVN 030923
AFDDVN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
323 AM CST WED FEB 3 2016

.SYNOPSIS...
ISSUED AT 323 AM CST WED FEB 3 2016

OCCLUDED WINTER STORM SYSTEM LIFTING INTO THE GREAT LAKES HAD A
DOUBLE LOW STRUCTURE WITH ONE LOW OVER SW LOWER MI AND THE OTHER
JUST NW OF CEDAR RAPIDS AT 2 AM. THE UPPER LEVEL TROUGH REACHED
FROM MN SOUTH INTO CENTRAL IA. UNDER THIS FEATURE...A RELATIVELY
NARROW AXIS OF MODERATE TO HEAVY SNOW EXTENDED FROM THE DES MOINES
AREA NW THROUGH WATERLOO INTO NE IA. OVER THE PAST SEVERAL
HOURS...THIS FEATURE HAS BEGUN TO SHOW A WEAKENING NATURE...AS
PREDICTED BY SHORT TERM MODELS...AS IT WAS ROTATING E-SE TOWARD
EASTERN IA. ELSEWHERE...WIDESPREAD DENSE FOG THAT FORMED UNDER THE
ELEVATED DRY SLOT AND LIGHT WIND FIELDS IN THE WARM SECTOR OF THE
EASTERN IA LOW...WAS CLEARING FROM SOUTH TO NORTH AS SW WINDS
ROTATING AROUND THE BASE OF THE EASTERN IA LOW WAS ADVECTING DRIER
AIR INTO THE AREA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 323 AM CST WED FEB 3 2016

FOCUS REMAINS ON FOG AND ANOTHER ROUND OF WINTER WEATHER BEFORE
THE WINTER STORM SYSTEM EXITS THE REGION TODAY.

EARLY THIS MORNING...FOG WAS MAINLY CONFINED TO AREAS NORTH OF
INTERSTATE 80 AND EAST OF THE HIGHWAY 218 CORRIDOR. THE REMAINING
SEGMENT OF THE DENSE FOG ADVISORY FOR EAST CENTRAL IA INTO NW IL
TIL 6 AM MAY BE FURTHER TRIMMED AS WINTRY PRECIPITATION MOVES INTO
EAST CENTRAL IA. ALONG AND EAST OF THE MS RIVER...THE REMAINING
SEGMENT LOOKS GOOD FOR NOW.

THE WINTER WEATHER ADVISORY ISSUED LAST EVENING IN PLACE FOR THE
HIGHWAY 20 CORRIDOR IN EASTERN IA...INTO BENTON COUNTY WILL REMAIN
UNCHANGED. THE AXIS OF SNOW IN CENTRAL IA REACHING INTO
INDEPENDENCE AND VINTON...WHILE WEAKENING AND NARROWING...MAY LAY
OUT A QUICK 1 TO POSSIBLY 3 INCHES ESPECIALLY IN BUCHANAN COUNTY
BEFORE DAWN. INCREASING NW WINDS MAY ALSO RESULT IN BLOWING
SNOW WHICH COULD EXTEND BEYOND THE CURRENT ADVISORY PERIOD. WILL
LEAVE THE 12Z/6 AM EXPIRATION TIME INTACT FOR NOW...BUT WILL
MONITOR CONDITIONS FOR A POSSIBLE EXTENSION.

OTHERWISE...POSSIBLE MIXED PRECIPITATION WILL OCCUR FURTHER SOUTH
EARLY THIS MORNING CHANGING OVER TO LIGHT SNOW AND ENDING BY MID
MORNING AS THE DEFORMATION AXIS LIFTS NORTHEAST. BRISK NW WINDS OF
20 TO 30 MPH WILL OVERSPREAD THE AREA WITH COLD ADVECTION
LOWERING TEMPERATURES INTO THE 20S BY MID TO LATE AFTERNOON. THE
LINGERING CYCLONIC FLOW MAY PRODUCE AT LEAST FLURRIES...WHICH HAVE
BEEN INCLUDED ACROSS THE EAST THROUGH MID AFTERNOON. OVERNIGHT...A
RIDGE OF HIGH PRESSURE MOVES IN...BUT THE POTENTIAL FOR CLEARING
LOOKS QUESTIONABLE UNDER THE CYCLONIC FLOW ALOFT. COUNTING ON
MOSTLY CLOUDY SKIES...WILL HOLD LOWS IN THE TEENS TO NEAR 20.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 323 AM CST WED FEB 3 2016

MAIN FORECAST CONCERN IN THE LONG TERM ARE A SERIOUS OF CLIPPERS
THAT WILL AFFECT THE REGION THROUGH EARLY SATURDAY AND THEN A MORE
SUBSTANTIAL STORM EARLY NEXT WEEK AS NW FLOW DUMPS COLDER AIR INTO
THE REGION.  SNOW CHANCES THROUGH SATURDAY WILL BE LOW WITH LITTLE
TO NO ACCUMULATION POSSIBLE.  A SERIES OF CLIPPERS FOLLOWING AFTER
EACH OTHER WILL BRING CHANCES FOR SNOW BACK TO THE AREA NEXT WEEK
AND TEMPERATURES THAT ARE MORE REMINISCENT OF WINTER.

A CLIPPER ON THURSDAY WILL PASS THROUGH NORTHERN WISCONSIN AND THE
UP OF MICHIGAN.  SPECTRAL MODELS ATTEMPT TO BRING WEAKENING QPF INTO
THE AREA THURSDAY AFTERNOON.  AFTER LOOKING AT THE DGZ AND FORCING
IT APPEARS THAT THERE IS NO COHERENT FORCING WITHIN THE SATURATED
AIR.  AS SUCH WILL LEAVE OUT THE MENTION OF SNOW AND EVEN FLURRIES
AT THIS TIME.

FRIDAY NIGHT...ANOTHER CLIPPER WILL ACTUALLY CROSS THE CWA.  LIMITED
MOISTURE AGAIN AND WEAK FORCING PRECLUDES MUCH DEVELOPMENT OF SNOW.
A SFC LOW AND CONVERGENCE IN THE SE SIDE OF THIS LOW LOOKS TO BE
ENOUGH TO CAUSE LIGHT SNOW ACROSS SOUTHERN AND SOUTHEASTERN ZONES ON
FRIDAY NIGHT.  AT THIS TIME HAVE SLIGHT POPS ACROSS THE AREA AS LLVL
SATURATION LOOKS TO BE A PROBLEM WITH DRY AIR.  THERE APPEARS TO BE
A STRONG FORCING ALOFT AT H8...WHICH IS RIGHT BELOW THE DGZ.  THIS
COUPLED WITH THE DRY LLVL LEADS ME TO THE SCHC POPS AT THIS TIME.

THIS WEEKEND A WARMUP OCCURS WITH RATHER QUIET WEATHER.  THERE IS A
SCHC FOR RAIN ON SUNDAY AS THE NEXT SYSTEM APPROACHES THE AREA.  A
DUMP OF COLD AIR MOVES IN FOR THE BEGINNING OF THE WEEK ALONG WITH
THE CHANCES FOR SNOW.  AT THIS TIME...THE GFS AND ECMWF ARE OFFERING
DIFFERING H85 TEMPS WITH THE GFS BEING CLOSE TO -25C AND THE ECMWF
NEAR -12C.  OBVIOUSLY THIS WILL GREATLY AFFECT TEMPS WITH THE DUMP.
AT THE TIME EXPECT TEMPS TO BE A COMPROMISE OF THE TWO.  THE BEST
CHANCE FOR SNOW APPEARS TO BE WITH THE FROPA MONDAY AFTERNOON INTO
TUESDAY.  REGARDLESS...EXPECT SOME KIND OF SNOW AND COLDER
TEMPERATURES FOR NEXT WEEK.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1149 PM CST TUE FEB 2 2016

ANTICIPATE VLIFR DENSE FOG TO LIFT OVERNIGHT AS WINDS INCREASE
WITH MAINLY IFR TO MVFR CONDITIONS TO FOLLOW THROUGH MID AM
ALTHOUGH PERIOD OF VFR POSSIBLE AT BRL AND MLI. SNOW OVER CENTRAL
IA TO ROTATE ACROSS MAINLY NORTHEAST IA OVERNIGHT THROUGH DAYBREAK
WITH PERIOD OF ACCUMS AT CID AND DBQ WITH HEAVIEST NORTHWEST OF
THESE TERMINALS. MORE SHOWERY PRECIP POSSIBLY A MIX TO GO OVER TO
PERIOD OF LIGHT SNOW OR FLURRIES AND BRL AND MLI WED AM FOR A
TIME. EXPECT THE PRECIPITATION TO END BY MID TO LATE AM AND
CONDITIONS TO LIFT TO MVFR FOR CIGS... WITH WINDS GUSTY FROM THE
NORTHWEST AT 15 TO 30 KTS. BLOWING SNOW UNCERTAIN AT DBQ AND CID
AND THUS LEFT OUT MENTION. POSSIBLE TO SEE SOME IMPROVEMENT TO
VFR LATE IN THE TAF PERIOD... BUT OPTED TO STAY ON PESSIMISTIC
SIDE FOR NOW.


&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...DENSE FOG ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR CLINTON-
     JACKSON-JONES-LINN.

     WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
     BENTON-BUCHANAN-DELAWARE-DUBUQUE.

IL...DENSE FOG ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR CARROLL-
     JO DAVIESS-STEPHENSON-WHITESIDE.

MO...NONE.
&&

$$

SYNOPSIS...SHEETS
SHORT TERM...SHEETS
LONG TERM...GIBBS
AVIATION...05



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