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000
FXUS63 KDVN 182144
AFDDVN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
444 PM CDT TUE JUN 18 2013

.UPDATE...
ISSUED AT 442 PM CDT TUE JUN 18 2013

A FAIRLY SIGNIFICANT POP/WX/SKY/TEMP/WIND/SKY UPDATE WAS SENT JUST
PRIOR TO 420 PM TO REFLECT A DRY FORECAST EXCEPT FOR THE FAR
SOUTHWESTERN CWA. I DO NOT EXPECT STRONG CONVECTION TO BE
SUSTAINED IN OUR CWA...BUT THE THIS AREA COULD SEE SOME
DISSIPATING SHOWERS AS THE MOVE FROM DMX/S CWA. SKIES ARE NEARLY
CLEAR NOW IN MOST LOCATIONS...AND WILL CONTINUE TO CLEAR. A
PERFECT NIGHT FOR OUTDOOR ACTIVITIES SHOULD GREET THOSE WHO
VENTURE OUTSIDE TONIGHT.

ERVIN

&&

.SYNOPSIS...
ISSUED AT 221 PM CDT TUE JUN 18 2013

SEASONABLY STRONG BACKD0OR COLD FRONT BRINGING REFRESHINGLY
COMFORTABLE AIR INTO THE FORECAST AREA UNDER MOSTLY SUNNY SKIES.
AREA TEMPERATURES AT 2 PM ARE IN THE MID TO UPPER 70S WITH DEWPOINTS
ON THE 50S TO LOWER 60S SOUTH ON NE WINDS OF 5 TO 15 MPH. UPSTREAM
ANALYSIS SHOWS HIGH NOW NORTHERN WISCONSIN TO SLIDE INTO OHIO
VALLEY BY WEDNESDAY EVENING BRINGING A WARMING TREND AND HIGHER
DEWPOINTS STARTING LATE WEDNESDAY AFTERNOON. UPSTREAM ANALYSIS
SHOWS TYPICAL MID SUMMER ZONAL FLOW WITH TEMPERATURES SLIGHTLY
ABOVE TO ABOVE NORMAL WITH A RISK OF THUNDERSTORMS LATE THIS WEEK
INTO NEXT WEEK.

&&

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 221 PM CDT TUE JUN 18 2013

TONIGHT...WEAK HIGH PRESSURE EXTENDING FROM LAKE MICHIGAN TO ALLOW FOR
COOL MINS UNDER A CLEAR TO MOSTLY CLEAR SKY AND LIGHT EAST WINDS.
LOCAL TOOLS SUGGEST UPPER 40S IN FAVORED LOW LYING LOCATIONS IN NE
1/3 OF THE AREA AND LOWER TO MIDDLE 50S ELSEWHERE. NICE WEATHER
FOR OPENING WINDOWS.

WEDNESDAY...ANOTHER NICE WITH FAIR SKIES AND LIGHT EAST WINDS BECOMING
SOUTHEAST BY MID DAY. HIGHS A FEW DEGREES HIGHER THAN TODAY
RANGING FROM 77 NE TO 83 SW SECTIONS.

NICHOLS

.LONG TERM...(WEDNESDAY NIGHT THROUGH NEXT TUESDAY)
ISSUED AT 221 PM CDT TUE JUN 18 2013

WEDNESDAY NIGHT AND THURSDAY...THE MEAN TRENDS ON THE LATEST 12Z RUNS
SUGGEST SEASONABLY STRONG WESTERN GRT LKS ANTICYCLONE TO START TO
WEAKEN AND MIGRATE EASTWARD THIS PERIOD...WHILE UPPER RIDGING
STARTS TO GET SQUEEZED/AMPLIFIED ACRS THE PLAINS IN RESPONSE TO
PACIFIC NORTHWEST LARGE UPPER CYCLONE/TROF COMPLEX BUILDING INLAND.
RIDGE-UNDERCUTTING WAVE ENERGY WILL UTILIZE SOME ELEVATED RETURN
FLOW TO PRODUCE CONVECTION ACRS THE CENTRAL INTO NORTHERN PLAINS/MO
RVR VALLEY REGIONS...BUT WED NIGHT SHOULD STAY DRY LOCALLY WITH
JUST SOME DEBRIS CLOUDS DRIFTING INTO THE WESTERN CWA. LOWS
IN THE MID 50S IN THE NORTHEAST...TO THE LOWER 60S WEST. THE
PLUME OF ELEVATED RETURN FLOW/WARM AIR ADVECTION SHOULD TRY TO ADJUST
EASTWARD ON THU...ALONG WITH LLVL WARM FRONT TRYING TO RETREAT
NORTHWARD OUT OF MO AND UP ACRS THE DVN CWA. ALTHOUGH LOWER LEVEL
FORCING APPEARS TO BE NOT ALL THAT GREAT ATTM...WILL KEEP CHC POPS
GOING ALL DAY. DEPENDING ON CLOUD DEBRIS AND BOUNDARY PLACEMENT...
HIGH TEMPS FOR THU TRICKY WITH LARGE VARIATIONS ACRS THE LOCAL AREA
POSSIBLE. WILL LEAN TOWARD CLIMO FOR TEMPS FOR NOW. TAKING MEDIUM
RANGE MODEL BLEND...IT APPEARS BULK OF NOCTURNAL MCS INDUCING
PARAMETERS WILL SET UP ACRS THE MO RVR VALLEY INTO WESTERN MN THU
NIGHT...BUT SECONDARY SUPPORT ZONE FOR AN ELEVATED WING OF
CONVECTION OR EVEN A TYPE OF MCS MAY TRY TO DEVELOP ACRS NORTH
CENTRAL IA AND INTO THE DVN CWA LATE THU NIGHT. THE LATEST RUN 12Z
ECMWF CONTINUES TO BE THE MOST BULLISH MODEL WITH THIS IDEA...WHILE
THE 12Z RUN GFS WITH IT/S HIGH AMPLIFICATION OF THE UPPER RIDGE
SHUNTS EVERYTHING WELL TO THE NORTH AND NORTHWEST...KEEP THE DVN
CWA DRY INTO FRI MORNING. WILL HAVE TO KEEP CHC POPS GOING ESPECIALLY
IN THE NORTHWESTERN HALF OF THE DVN CWA CLOSER TO ELEVATED THTA-
TRANSPORT WING.

FRIDAY AND SATURDAY...SO STARTS THE PERIOD OF WHAT HAPPENS THE DAY OR
PERIOD BEFORE WILL GREATLY IMPACT THE NEXT DAY. THE ECMWF SUGGESTS
THAT MORNING MCS REMNANTS WILL DECAY DIURNALLY AND ENHANCE A
WEST-TO-EAST BOUNDARY IN PLACE ACRS THE DVN CWA OR VERY CLOSE...
MAKING A FOCAL POINT FOR MORE LATE DAY AND NIGHT CONVECTION TO FIRE
ON. AGAIN IF THIS OCCURS...IT APPEARS WILL BE A SECONDARY CONVECTIVE
ZONE WITH MAIN FORCING IN SOUTHWESTERLY WAVE TRAIN ACRS THE NORTHERN
PLAINS. RING OF FIRE PATTERN ESTABLISHING ACRS THE NORTHERN
PLAINS/UPPER MIDWEST INTO THE GRT LKS...BUT HOW FAR NORTH OR SOUTH
THE PRIME MCS AXIS LAYS OUT STILL UNCERTAIN AT THIS TIME. THE GFS
MAINTAINS HIGH AMPLITUDE NORTHERLY BIAS WITH THE DVN CWA MAINLY DRY
FRI NIGHT THROUGH SUNDAY MORNING...WHILE MCS/S RAGE ACRS THE
DAKOTAS...MN INTO WI AND THE U.P. OF MI. THE GFS ALSO BUILDS A HIGH
CAPE AIRMASS/POOL LOCALLY WITH HIGHS IN THE LOW TO MID 90S AND DPTS
IN THE 70S. BUT THE ECMWF AND GEM ARE MORE OMINOUS WITH A LOWER
AMPLITUDE UPPER RIDGE AND FURTHER SOUTH LLVL BAROCLINICITY/STORM
TRACK. THESE MODELS WOULD PUT US ON THE FRINGE OR UNDER THE DIRECT
PATH OF ONE OR MORE MCS/S FRI NIGHT AND AGAIN SAT NIGHT. EACH ONE
WOULD HAVE THE CAPABILITY OF PRODUCING HEAVY RAINFALL AND POSSIBLY
SOME SVR WX...ESPECIALLY THE SAT EVENING/NIGHT COMPLEX IF IT
MATERIALIZES CLOSE ENOUGH TO IMPACT THE LOCAL AREA AND FEED ON A HIGH
CAPE AIRMASS. NEEDLESS TO SAY WITH THE POTENTIAL SHOWN BY THE ECMWF
AND GEM...WILL HAVE TO KEEP DECENT CHC POPS GOING THROUGH THE WEEKEND
ESPECIALLY THE NORTH HALF. WILL GO IN BETWEEN THE GFS AND ECMWF HIGH
TEMP POTENTIAL FOR SAT WITH UPPER 80S TO NEAR 90 WITH BUILDING HEAT
INDICES IF DPTS CAN GET INTO AT LEAST THE LOWER 70S. GFS MID 70 SFC
DPTS FOR SAT APPEAR OVERDONE AND PRODUCE 5K+ J/KG SBCAPES BY LATE SAT
AFTERNOON.

SUNDAY THROUGH NEXT TUESDAY...LONGER RANGE INDICATIONS SUGGEST THE
DVN CWA TO LIE VERY CLOSE TO ONGOING RING OF FIRE PATTERN ACRS THE
UPPER MIDWEST WITH ALMOST DAILY CHANCES FOR STORMS TO FIRE IN THE
LOCAL AREA OR POSSIBLY BLEED INTO THE CWA FROM THE WEST OR NORTHWEST
LATE AT NIGHT. SUPPOSE A LOW CHC THAT MOST OF THE ACTIVITY MAINTAINS
TO THE NORTH ACRS THE DAKOTAS/MN AND WI WHILE WE REMAIN HOT AND
CAPPED THROUGH TUE...BUT ODDS ARE A STORM COMPLEX WILL AT LEAST
GLANCE THE CWA SOMETIME IN THIS EXTENDED PERIOD...POSSIBLY A
SIGNIFICANT CAPE EATING STORM COMPLEX IF 18 TO 23 C H85 MB TEMP
GRADIENT CAN SAG THROUGH THE REGION. CLIMATICALLY NORMAL/TYPICAL MID
SUMMERTIME PATTERN LOOKS TO BE IN STORE.    ..12..

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 221 PM CDT TUE JUN 18 2013

VFR CONDITIONS TO CONTINUE THROUGH AT LEAST 20/00Z. WEAK HIGH
PRESSURE OVER THE GREAT LAKES ARE BRINGING SEASONABLY COOL
TEMPERATURES AND FAIR SKIES. LIGHT NE WINDS THIS PM WILL SHIFT TO
THE SE WEDNESDAY. AREA VISIBILITIES WILL STAY ABOVE 7 MILES.

NICHOLS


&&

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

$$

UPDATE...ERVIN
SYNOPSIS...NICHOLS
SHORT TERM...NICHOLS
LONG TERM...12
AVIATION...NICHOLS