Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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000
FXUS63 KDVN 100857
AFDDVN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
357 AM CDT THU JUL 10 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT THU JUL 10 2014

THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD IS THE TIMING OF
POTENTIAL STORMS IN THE WESTERN FORECAST AREA TONIGHT.

IN THE NEAR TERM...SURFACE HIGH PRESSURE REMAINS IN PLACE ACROSS THE
REGION WITH DEWPOINTS MAINLY IN THE 50S. EXPECT DRY CONDITIONS AGAIN
TODAY WITH AFTERNOON TEMPERATURES IN THE UPPER 70S NORTH TO LOWER
80S SOUTH...SLIGHTLY BELOW NORMAL FOR EARLY JULY.

THE FIRST IN A SERIES OF SHORT WAVE TROUGHS WILL MOVE INTO IOWA
TONIGHT. MODEL CONSENSUS HAS IMPROVED REGARDING THE TIMING OF THE
WAVE. MUCH OF THE FORECAST AREA IS NOW EXPECTED TO STAY DRY THROUGH
12Z FRIDAY. HAVE MAINTAINED CHANCE POPS ACROSS THE WEST AFTER
MIDNIGHT...WITH A NARROW SWATH OF LIKELY POPS WEST OF A LINE FROM
VINTON...TO WILLIAMSBURG AND KEOSAUQUA. NO SEVERE WEATHER IS
ANTICIPATED.


.LONG TERM...(FRIDAY THROUGH NEXT WEDNESDAY)
ISSUED AT 354 AM CDT THU JUL 10 2014

FRIDAY THROUGH SUNDAY...ASSESSING SEVERAL OF THE LATEST 00Z RUN
MODELS AND CONCEPTUAL PATTERN THAT THEY PAINT/ENSEMBLE IDEA...IT
APPEARS THE AREA COULD BE UNDER THE MCS GUN FOR A GOOD CHUNK OF THIS
PERIOD. BROAD UPPER RIDGING LAYS OUT TO ALMOST A ZONAL FLOW WITH
INCREASING WESTERLIES ACRS THE NORTHERN THIRD OF THE MID CONUS. THIS
TEMPORARY BEFORE A FLUX/PATTERN TRANSITION INTO DIGGING CYCLONIC
UPPER FLOW BY SUNDAY AS CANADIAN/WESTERN HUDSON BAY VORTEX SINKS
SOUTHWARD. WILL WALK UPSTREAM ELEVATED STORM CLUSTER OR EVEN AN MCS
TYPE SYSTEM ACRS EASTERN IA AND THE REST OF THE DVN CWA ON FRI IN
DIURNALLY WEAKENING FASHION. CONVECTIVE DEBRIS KEEPING TEMPS DOWN IN
THE 70S TO LOW 80S AT BEST. THEN THE LATEST SIGNALS OF THE 00Z RUN
SOLUTIONS SUGGEST WEST-TO-EAST LLVL BAROCLINICITY TO LAY OUT
PARALLEL TO UPPER LEVEL STEERING FLOW FROM ACRS NEB...IA AND INTO
NORTHERN IL BY SAT EVENING. REMNANT OUTFLOW BOUNDARY OR DEBRIS FROM
THE SYSTEM EARLIER ON FRI TO BE A PLAYER TO AND MAY MAKE FOR A FOCUS
A BIT FURTHER SOUTH THAN CURRENTLY ANTICIPATED. THE LLVL THERMAL
GRADIENT/S TO BE A FOCUS FOR DEVELOPING SOUTHWESTERLY LLJ OF 30-40+
KTS AND MOISTURE FEED TO RIDGE UP OVER...CONVERGE AND INDUCE
CONVECTION. AGAIN LATEST THINKING SUGGESTS THIS FRI EVENING
CONVECTION TO BLOSSOM ACRS NEB INTO WESTERN IA...WITH RESULTANT MCS
PROPAGATING EASTWARD ACRS THE LOCAL AREA LATE FRI NIGHT AFTER
MIDNIGHT. BUT SOME SIGNS OF INITIAL CONVECTION POSSIBLY TAKING OFF
FURTHER TO THE EAST ACRS CENTRAL IA INTO EASTERN IA WITH SOONER
ARRIVING VORT MAX ALOFT. MANY MODELS PAINT CENTRAL IA AND THE
NORTHERN HALF OF THE DVN CWA WITH HIGHER COVERAGE OF CONVECTION...
BUT AGAIN WONDER IF THEY MAY BE TOO FAR NORTH AND THAT THE
SOUTHERN CWA MAY BE MORE IN LINE. WILL BUMP UP POPS ACRS MUCH OF
THE AREA FOR NOW. EXTENT OF WARM MOIST CONVEYOR AND CONVERGENT
PWAT FEED OF OVER 1.7 INCHES SUGGEST LOCALLY HEAVY RAINFALL
POSSIBLE WITH ANY CONVECTIVE SYSTEM THAT CAN ORGANIZE AN MAKE IT
ACRS THE AREA...WELL OVER AN INCH BY SAT MORNING. CONVECTION MAY
THEN FESTER INTO PART OF SAT...WITH ASSOCIATED DEBRIS AND
BOUNDARIES UNDULATING ALL OVER THE PLACE. MUCH WILL DEPEND ON THE
POTENTIAL OF AIR MASS RECOVERY BY LATE SAT IN ONGOING WARM AIR
ADVECTION REGIME INTO THE AREA FROM CAPPED MOIST SOURCE REGION
JUST TO THE SOUTH ACRS THE SOUTHERN AND CENTRAL PLIANS...MO/AR
INTO THE WESTERN OH RVR VALLEY. THE DIGGING UPPER TROF AXIS
MENTIONED ABOVE AND CYCLONIC MID TO UPPER LEVEL JET ENERGY
PUNCHING DOWN ACRS THE UPPER MIDWEST WILL PROVIDE DECENT FORCING
SET UP ALONG WITH MORE ENHANCED SHEAR PROFILES SAT NIGHT FOR A
POSSIBLE SVR MCS TO IMPACT PORTIONS OR MOST OF THE LOCAL FCST
AREA. MORE HEAVY RAIN TO ALSO THINK ABOUT OF AT LEAST 1-2+ INCHES
BY SUNDAY MORNING. THIS BOUT OF RAIN COMBINED WITH WHATEVER OCCURS
FRI NIGHT INTO EARLY SAT COULD REALLY ADD UP TO SIGNIFICANT
AMOUNTS BY THE END OF THE WEEKEND...PRODUCING FLASH FLOODING...
RENEWED RIVER/STREAM FLOODING OR AGGRAVATING ONGOING RIVER
FLOODING SITUATIONS. THE LATEST SOLUTIONS DO SUGGEST THAT AFTER
ANY LINGERING CONVECTIVE COMPLEXES EXIT THE AREA OR GET SHUNTED TO
THE SOUTH AND SOUTHEAST OF THE REGION SUNDAY MORNING...JUST SCTRD
AND MUCH LESS ORGANIZED AREAS OF PRECIP MAY OCCUR LATER SUNDAY
INTO MON MORNING. TEMPS A CHALLENGE OVER THE WEEKEND BUT THERE IS
THE POTENTIAL FOR PORTIONS OF THE AREA TO SUBSTANTIALLY HEAT UP
AND BECOME MUCH MORE HUMID. BUT AGAIN CONVECTIVE DEBRIS AND
BOUNDARIES COULD REALLY MESS UP HIGH TEMP FCSTS AND WILL PLAY AN
AVERAGE FROM NORTH TO SOUTH FOR NOW.

MONDAY THROUGH NEXT WEDNESDAY...LATEST MEDIUM RANGE SOLUTIONS
CONTINUE WITH THE IDEA...AND THE 00Z RUN GFS HAS COME ON BOARD
BIG TIME...ABOUT LARGE COLD CORE VORTEX/COOL SEASON LOOKING
PATTERN SET UP ACRS THE CENTRAL INTO EASTERN CONUS NEXT WEEK.
SEVERAL SOLUTIONS ARE ADVERTISING A DEEP L/W UPPER TROF ACRS THE
GRT LKS WITH MERIDIONAL FLOW DOWN THE UPPER MIDWEST OUT OF
CANADA/NORTHWESTERN HUDSON BAY REGION. THE MAIN STORM TRACK COULD
BE SHUNTED ALL THE WAY DOWN TO THE GULF...WHILE THE UPPER
MIDWEST/NORTHERN PLAINS GET INUNDATED WITH UNSEASONABLY STRONG
CANADIAN HIGH PRESSURE SYSTEMS AND COLD AIR. BOTH THE GFS AND
ECMWF NOW ADVERTISE SINGLE DIGIT H85 MB TEMPS INTO OR VERY CLOSE
TO THE DVN CWA FROM MON NIGHT THROUGH AT LEAST NEXT WED. IF ENOUGH
CLOUD COVER...SOME SIGNS THAT HIGH TEMPS DURING FROM TUE INTO
WED/MID NEXT WEEK MAY STRUGGLE TO GET OUT OF THE 60S...AND RECORD
OR NEAR RECORD LOW TEMPS POSSIBLE OVERNIGHT IF SKIES CLEAR OUT AND
SFC WINDS DECREASE ENOUGH. WILL TREND DOWN TEMPS AT THE END OF THE
EXTENDED PERIOD FOR NOW...AND AWAIT ANY FURTHER MODEL OR
TELECONNECTION AGREEMENT IN THE RUNS OVER THE NEXT FEW DAYS. ..12..

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY EVENING)
ISSUED AT 624 PM CDT WED JUL 9 2014

IDEAL AVIATION WEATHER WILL CONTINUE THROUGH THURSDAY
EVENING...AS LIGHT NORTHWEST WINDS OVERNIGHT BECOME SOUTH AROUND
10 TO 12 KTS BY MID MORNING THURSDAY. OTHER THAN THIS WIND
SWITCH...CONTINUOUS VFR/CLEAR WEATHER IS EXPECTED. I HAVE BROUGHT
IN SOME MID CLOUDS AROUND 03Z/11 TO INDICATE THE FIRST WAVE OF
WARM ADVECTION...THIS WARM ADVECTION IS EXPECTED TO BRING SHOWERS
AND STORMS TO THE REGION LATE THURSDAY NIGHT AND FRIDAY.

ERVIN

&&

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

$$

SHORT TERM...RP KINNEY
LONG TERM...12
AVIATION...ERVIN






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