AP-IL--DBQ-IL NW Area Forecast Discussion, IL
000
FXUS63 KDVN 151145
AFDDVN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
645 AM CDT WED JUL 15 2015
.SYNOPSIS...
ISSUED AT 307 AM CDT WED JUL 15 2015
AT 3AM CDT...SIMILAR SET UP TO LAST NIGHT...SFC HIGH PRESSURE
CENTER POSITIONED OVER THE NORTHERN GREAT LAKES AND LIGHT EASTERLY
FLOW OVER E IOWA/NW ILLINOIS. THE STEADY EASTERLY WINDS HAVE
BROUGHT DRY AIR...WITH DEWPOINTS DOWN INTO THE 50S...INTO THE
EASTERN CWA MOSTLY ALONG AND EAST OF THE MISSISSIPPI RIVER.
FURTHER WEST...DEWPOINTS WERE STILL GENERALLY IN THE 60S AND TEMPS
WERE IN THE UPPER 60S TO LOWER 70S. EXPECT DRIER AIR TO CONTINUE
TO WORK ITS WAY WESTWARD THROUGH THIS MORNING.
CLOSEST AREAS OF CONVECTION WERE OVER NE NEBRASKA AND NORTH-
CENTRAL KANSAS...THE LATTER BEING MUCH MORE ROBUST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT WED JUL 15 2015
TODAY...EXCEPTIONALLY NICE WEATHER FOR THE MIDDLE OF JULY WITH
COMFORTABLE DEWPOINTS IN THE 50S/60S. HIGHS IN THE UPPER 70S OVER
NE IOWA/NW ILLINOIS...NEAR 80 F AROUND THE QUAD CITIES...AND IN
THE LOWER TO MIDDLE 80S FOR SE IOWA/NE MISSOURI.
TONIGHT...SHORTWAVE TROUGH OVER THE PLAINS WILL MOVE ENE TOWARD
IOWA. MODEL TREND OVER PAST SEVERAL RUNS HAS BEEN TO SLOW THE
ONSET OF PRECIP INTO E IOWA/NE MISSOURI...AND ALSO FOCUS THE
STEADIER RAIN/THUNDERSTORMS TO THE NORTHWEST OF THE DVN CWA WHERE
THE 850MB WAA BULLSEYE IS LOCATED. BEST CHANCE FOR SHOWERS/STORMS
WILL BE AFTER 3-4 AM CDT. CURRENT PRECIP FORECAST BY 7 AM CDT
THURSDAY IS FOR 60 POPS OVER THE FAR WESTERN COUNTIES TAPERING TO
20 POPS ALONG THE MISSISSIPPI RIVER.
850MB MOISTURE ADVECTION PLOTS INDICATE STRONG VALUES LATE TONIGHT
INTO THURSDAY AFTN...BUT THERE WILL BE A DELAYED RESPONSE IN THE
INCREASE OF INSTABILITY UNTIL AT LEAST MID THURSDAY MORNING. IN
OTHER WORDS...LOW INSTABILITY UP TO EARLY THURSDAY MORNING WILL
PRECLUDE A SEVERE WEATHER THREAT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 307 AM CDT WED JUL 15 2015
A MATURE TO DECAYING CONVECTIVE COMPLEX SHOULD MOVE ACROSS THE
NORTHERN HALF OF THE AREA ON THURSDAY WITH THE BETTER CHANCES OF
RAIN ALONG/NORTH OF HIGHWAY 30. BOUNDARIES CREATED BY THIS COMPLEX
WILL THEN PROVIDE THE FOCUS FOR DIURNAL CONVECTION THURSDAY
AFTERNOON/EVENING. PRECIPITATION/CLOUD COVER WILL DETERMINE
TEMPERATURES THURSDAY BUT THERE COULD BE A 15 DEGREE GRADIENT IN
HIGHS ACROSS THE AREA.
LINGERING DIURNAL CONVECTION WILL PERSIST INTO THE EARLY EVENING
ACROSS THE AREA AND THEN DISSIPATE. THE MODELS DO SHOW A WEAK UPPER
LEVEL DISTURBANCE MOVING THROUGH LATE THURSDAY NIGHT/EARLY FRIDAY
MORNING THAT COULD PRODUCE SOME ISOLATED SHOWERS AND MAYBE A
THUNDERSTORM AS THE WARM FRONT MOVES THROUGH THE AREA.
VERY WARM AND HUMID CONDITIONS WILL BE SEEN ACROSS MOST OF THE AREA
ON FRIDAY. THE EXCEPTION MAY BE THE HIGHWAY 20 CORRIDOR. BASED ON
THE FORECAST HIGHS AND DEW POINTS...HEADLINES FOR HEAT WOULD
EVENTUALLY BE NEEDED ALONG/SOUTH OF I-80 DURING THE AFTERNOON/EARLY
EVENING.
THERE MAY OR MAY NOT BE ISOLATED DIURNAL CONVECTION DEVELOP FRIDAY
AFTERNOON OVER THE NORTHEAST QUARTER OF THE AREA AS A WEAK UPPER
LEVEL DISTURBANCE MOVES THROUGH THE AREA.
FRIDAY NIGHT ANOTHER UPPER LEVEL DISTURBANCE MOVES THROUGH THE
SOUTHERN PARTS OF MINNESOTA AND WISCONSIN. THE PROXIMITY OF THE WARM
FRONT FROM FAR NORTHERN IOWA TO NEAR DETROIT WOULD SUPPORT THE
POTENTIAL FOR ISOLATED TO SCATTERED CONVECTION ACROSS THE NORTHERN
THIRD OF THE AREA AND POSSIBLY DOWN TO I-80.
SATURDAY ON...THE MODELS CONTINUE TO VARY IN THEIR RESPECTIVE
SOLUTIONS ON THE PLACEMENT AND TIMING OF FRONTS AND DISTURBANCES
ALOFT. AS SUCH THE MODEL CONSENSUS HAS SLIGHT CHANCE TO CHANCE
POPS SATURDAY THROUGH SUNDAY NIGHT. TEMPERATURES SATURDAY WILL
AGAIN BE VERY WARM AND HUMID WITH HEAT INDEX READINGS APPROACHING
100. DEPENDING UPON THE ARRIVAL OF THE COLD FRONT...SUNDAY MAY BE
SLIGHTLY COOLER BUT HEAT INDEX READINGS WOULD STILL BE 95 TO 100
FOR MUCH OF THE AREA.
WHAT OCCURS ON MONDAY WILL DEPEND UPON WHEN THE COLD FRONT MOVES
THROUGH. THE VARIOUS MODEL SOLUTIONS RUN FROM DRY MON/MON NIGHT TO
WET WITH THE FRONT MOVING THROUGH THE AREA. AS SUCH THE MODEL
CONSENSUS HAS SLIGHT CHANCE TO CHANCE POPS MONDAY AND SLIGHT CHANCE
POPS MONDAY NIGHT. MONDAY WILL BE COOLER AND SOMEWHAT LESS HUMID.
TUESDAY IS CURRENTLY LOOKING DRY WITH HIGH PRESSURE MOVING THROUGH
THE MIDWEST. TEMPERATURES LOOK TO BE SLIGHTLY BELOW NORMAL WITH MUCH
LESS HUMID CONDITIONS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 634 AM CDT WED JUL 15 2015
ZONE OF EARLY MORNING IFR/LIFR LOW CLOUDS AT KCID/KBRL...AND EVEN
SOME BR AT KCID...WILL DISSIPATE OVER THE NEXT HOUR. BROAD HIGH
PRESSURE AND A RELATIVELY DRY AIRMASS WILL CAUSE VFR CONDITIONS TO
PREVAIL THROUGHOUT THIS TAF PERIOD.
THE ONLY MENTION OF PRECIP WAS VCSH AT KCID AFTER 09Z/THU. AN
UPPER WAVE IS EXPECTED TO HAVE MORE OF AN IMPACT ON THE AREA IN
THE FORM OF SCT SHRA/TS BEYOND THIS FORECAST PERIOD.
UTTECH
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...UTTECH
SHORT TERM...UTTECH
LONG TERM...08
AVIATION...UTTECH
Delivered by Weather Underground Inc. Wed Jul 15 2015 7:46AM EDT