000
FXUS63 KLOT 191808
AFDLOT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
108 PM CDT WED JUN 19 2013

.DISCUSSION...
330 AM CDT

METEOROLOGICALLY BORING WEATHER ON TAP FOR THE NEXT COUPLE OF DAYS
WITH THE ONLY REAL FORECAST CHALLENGE THIS MORNING BEING TEMPS AND
CONVECTIVE CHANCES FRIDAY THROUGH THE WEEKEND AND INTO NEXT WEEK.

HIGH PRESSURE OVER THE REGION TODAY WILL SET THE STAGE FOR A STELLAR
DAY WITH AMPLE SUNSHINE...LOW HUMIDITY...MILD TEMPERATURES (ALBEIT
COOLER LAKESIDE) AND FAIRLY LIGHT WINDS. HIGH PRESSURE WILL MOVE OFF
TO THE EAST THE NEXT COUPLE DAYS WITH WINDS GRADUALLY TURNING MORE
SOUTHERLY ON THE BACK SIDE OF THE HIGH AND ALLOWING FOR A STEADY
WARM UP EACH OF THE NEXT FEW DAYS.

POWER-HOUSE UPPER LOW OFF THE PAC NW COAST WILL MOVE SLOWLY INLAND
AND GRADUALLY INCH ITS WAY EASTWARD INTO THE NORTHERN ROCKIES LATER
THIS WEEK AND INTO THE WEEKEND. DOWNSTREAM OF THIS UPPER LOW LOOK
FOR RIDGING ALOFT TO BUILD...THOUGH HOW FAR NORTH THE HEART OF THE
UPPER RIDGE BUILDS IS UP FOR DEBATE AMONG THE VARIOUS MODELS. GFS
HAS BEEN AND CONTINUES TO BE THE STRONGEST/FARTHEST NORTH WITH THE
UPPER RIDGE AND WOULD LIKELY SPELL HOT...HUMID AND RELATIVELY RAIN
FREE WX THROUGH THE WEEKEND. ECMWF CONTINUES TO BE A BIT WEAKER WITH
UPPER RIDGE WITH STRONGER BELT OF WESTERLIES CLOSER TO THE AREA AND
POSSIBLY LEAVING OUR CWA IN THE LINE OF FIRE FOR THE RING OF FIRE
PATTERN AND POTENTIAL FOR A COUPLE MCS TO ROLL THROUGH THE AREA.

PREVIOUS FEW FORECASTS HAVE BEEN LEANING A BIT TOWARD THE DRIER AND
STEAMIER GFS SOLUTION...AND WITH NO APPRECIABLE CHANGE IN THE MODEL
GUIDANCE THIS SET OF RUNS DIDNT SEE ANY GOOD REASON TO CHANGE
COURSE FROM OUR GOING FORECAST. CERTAINLY LOWER THAN AVERAGE
CONFIDENCE AND SHOULD MCS TRAIN COME ROLLING THROUGH THEN HIGHS
WOULD LIKELY BE MUCH COOLER AND IN THE 80S...HOWEVER SHOULD THE
RING `O FIRE STAY TO OUR NORTH AND WE STAY CAPPED THEN HIGHS IN
THE 90S WOULD BE LIKELY. DOES APPEAR AS THOUGH THE GEM IS MORE IN
THE ECMWF`S MCS CAMP...SO IF THIS TREND CONTINUES LATER FORECASTS
MAY NEED TO BEEF UP POPS AND TRIM TEMPS SOMEWHAT.

IZZI

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 18Z...

* NONE

TRS

//DISCUSSION...UPDATED 18Z...

A LARGE AREA OF HIGH PRESSURE WAS CENTERED OVER LOWER MI EARLIER
THIS MORNING AND IS PROGGED TO BE OVER THE LOWER GREAT LAKES BY
THIS EVENING. WHILE THE THE MEAN CENTER OF THE ANTICYCLONE WILL
BE DRIFTING EASTWARD...HIGH RESOLUTION MODELS SHOW INDIVIDUAL
HIGH CENTERS OVER THE COOL WATERS OF LAKE MI...LAKE HURON/THE N
CHANNEL... AND LAKE ERIE THIS AFTERNOON. WITH THE WEAK LOW LEVEL
FLOW ACROSS THE REGION THIS LOOKS TO BE A GOOD FORECAST. THIS
WILL ALLOW THE TEMPERATURE DIFFERENTIAL AND RESULTING ONSHORE
WINDS OFF OF SOUTHERN LAKE MI TO SLIGHTLY MODIFY THE WEAK
SYNOPTIC FLOW WHICH WILL BE GRADUALLY VEERING TO ESE AND SE THIS
AFTERNOON AND EARLY THIS EVENING. HOWEVER...WITH THE LAKE
INFLUENCE WINDS WILL REMAIN OUT OF THE E TO ENE UNTIL AFTER
SUNSET.

WITH THE ANTICYCLONE MOVING ACROSS SOUTHERN NEW ENGLAND...LONG
ISLAND AND THE JERSEY SHORE DURING THE OVERNIGHT AND THU MORNING
WINDS ACROSS THE LOCAL AREA WILL VEER TO OUT OF THE SE AND THEN
THE S THOUGH ARE LIKELY TO FEEL THE INFLUENCE OF THE LAKE IN THE
AFTERNOON AND BACK TO OUT OF THE SSE AND SE.

DEW POINTS HAVE REMAINED BEEN RISING THROUGH THE MORNING IN
RESPONSE TO THE VERY SLOWLY VEERING SYNOPTIC LOW LEVEL FLOW AND
THE FLOW OFF OF SOUTHERN LAKE MI. WITH HEATING THIS HAS ALLOWED
CU TO DEVELOP JUST W OF ORD AND MDW AS THIS IS WHERE DEW POINTS A
FEW DEGREES F HIGHER THAN CLOSER TO THE LAKE.

OTHERWISE...MID AND UPPER LEVEL HIGHS RISING AS RIDGING BUILDS
ACROSS THE EASTERN PLAINS AND THE MS VALLEY NO SIGNIFICANT
WEATHER TO OCCUR TONIGHT AND MOST OR ALL OF THU THOUGH THERE IS A
SMALL CHANCE OF AN ISOLATED THUNDERSTORM LOCALLY DURING THE LATE
AFTERNOON-EARLY EVENING AS A SHORT WAVE TROUGH MOVES ACROSS MN
AND WESTERN WI.

TRS

//ORD AND MDW CONFIDENCE...UPDATED 18Z...

* HIGH CONFIDENCE ALL ELEMENTS.

TRS

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

THURSDAY NIGHT THROUGH FRIDAY NIGHT...VFR.
SATURDAY THROUGH TUESDAY...PERIODIC CHANCES FOR THUNDERSTORMS...ELSE
VFR.

BMD

&&

.MARINE...
243 AM CDT

HIGH PRESSURE IS CENTERED OVER THE CENTRAL GREAT LAKES REGION EARLY
THIS MORNING AND IS FORECAST TO MOVE SOUTHEAST TOWARDS THE MID
ATLANTIC COAST BY THURSDAY. MEANWHILE...WINDS AND WAVES HAVE ALREADY
DIMINISHED UNDER THE INFLUENCE OF THE HIGH...THUS WILL ALLOW
REMAINING SMALL CRAFT ADVISORIES TO EXPIRE WITH THE MORNING FORECAST
PACKAGE. WITH LIGHT FLOW IN PLACE TODAY...WINDS WILL BECOME OFFSHORE
THIS AFTERNOON AS LAKE BREEZES DEVELOP ACROSS THE ENTIRE LAKE. AS
THE HIGH SETTLES TO OUR EAST THURSDAY...AND LOW PRESSURE OVER THE
PLAINS...WINDS WILL BEGIN TO TURN SOUTHERLY...AND FRESHEN UP FRIDAY
AS THE LOW LIFTS INTO THE UPPER MIDWEST. SOUTHERLY FLOW WILL
DOMINATE THE REMAINDER OF THE WEEKEND INTO EARLY NEXT WEEK. BMD

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$

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