343 PM CDT
ANOTHER TWO OR THREE DAYS OF DRY AND MILD WEATHER UNDER THE
INFLUENCE OF LIGHT SOUTHEASTERLY FLOW ARE IN STORE BEFORE A COLD
FRONT BRINGS A GOOD CHANCE OF RAIN TOWARD MIDWEEK. OCTOBER THEN
RETURNS AS WINDS GO NORTHWEST FOR THE REST OF THE WEEK INTO THE
WEEKEND.
EVEN BEHIND THE COLD FRONT...HIGHS ON THURSDAY SHOULD STILL REACH
THE MID 60S...WHICH IS NEAR AVERAGE FOR MID OCTOBER. FRIDAY AND
SATURDAY LOOK A BIT COOLER BEFORE TEMPERATURES APPEAR TO RECOVER
AGAIN BY NEXT SUNDAY. THIS TREND GENERALLY IS SUPPORTED BY ALL THE
DETERMINISTIC MODELS...THOUGH AN ALTERNATIVE SOLUTION FOR NEXT
SUNDAY IS GIVEN BY THE ECMWF...WHICH SHOWS ANOTHER UPPER WAVE AND
SURFACE LOW MOVING IN ON THE HEELS OF THE MIDWEEK SYSTEM.
THE LARGE PERSISTENT SURFACE RIDGE OVER THE EAST COAST FINALLY
STARTS TO BREAK DOWN AND MOVE INTO THE ATLANTIC BY LATE TUESDAY INTO
WEDNESDAY. PRIOR TO THAT TIME...SHORTWAVE ENERGY LIFTING OUT OF A
LONGWAVE TROUGH OVER THE MIDWEST WILL CONTINUE TO BE PUSHED UP AND
OVER THE EAST COAST UPPER RIDGE...NORTH OF OUR AREA. EVEN BY
TUESDAY AFTERNOON INTO EARLY WEDNESDAY THE RIDGE MAY CONTINUE TO
INHIBIT RAINFALL CHANCES FROM THE FRONT APPROACHING FROM THE WEST.
THE GULF NEVER REALLY APPEARS TO OPEN UP THIS WEEK...SO THE
FAVORABLE MID AND UPPER LEVEL DYNAMICS WITH THE APPROACHING SYSTEM
WILL HAVE TO OVERCOME RELATIVELY LOW DEWPOINTS AT LOW LEVELS. MODEL
PRECIP FIELDS ARE HINTING AT PREFRONTAL SHOWER ACTIVITY AS EARLY AS
WEDNESDAY AFTERNOON...BUT THIS COULD BE DELAYED INTO WEDNESDAY NIGHT
IF NOT AS LATE AS EARLY THURSDAY. THUS AM CARRYING INCREASED POPS
BUT ONLY CHANCE CATEGORY FOR NOW. MOST FAVORABLE PERIOD WOULD
APPEAR TO BE WEDNESDAY NIGHT INTO EARLY THURSDAY WHEN MODELS SHOW A
CLOSED UPPER AND SURFACE LOW DEVELOPING RIGHT OVER THE AREA.
CLOUDS AND POSSIBLY SOME SHOWERS WILL PERSIST THROUGH THURSDAY
BEFORE FRIDAY AND SATURDAY DRY OUT AGAIN UNDER COOL NORTHWEST FLOW.
SATURDAY MORNING COULD BE A BIT BRISK AND CHILLY FOR KIDS HEADING
OUT TO THE SPORTS FIELDS...BUT TRENDS SUGGEST SATURDAY AFTERNOON
WILL BE SOMEWHAT MORE COMFORTABLE.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 21Z...
* NONE
IZZI
//DISCUSSION...UPDATED 18Z...
BEAUTIFUL BLUE SKIES ARE WITH US FOR ANOTHER DAY AS THE RIDGE
REMAINS OVERHEAD. WINDS REMAIN LIGHT AND VARIABLE...BUT EXPECTING
WINDS TO TURN EAST THIS AFTERNOON AND REMAIN LESS THAN 10 KT.
A LAKE BREEZE HAS DEVELOPED FOR THE ENTIRE LOT
SHORELINE...AND THE BREEZE IS SLOWLY HEADING INLAND. THINKING WINDS
WILL ALREADY BE OUT OF THE EAST AT ORD AND MDW BY THE TIME THE
BREEZE REACHES THE TERMINALS. WINDS MAY PICK UP...BUT WILL STAY
BELOW 10 KT SO NOT EXPECTING A HUGE IMPACT FROM THE LAKE BREEZE
PASSAGE. WINDS WILL DIE DOWN TO BELOW 5 KT AFTER 00Z WHEN THE
SURFACE DECOUPLES. VFR CONDITIONS CONTINUE TOMORROW.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 21Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.
IZZI
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT THROUGH TUESDAY...VFR.
WEDNESDAY AND THURSDAY...CHC SHRA/SLGT CHC TSRA BRIEF MVFR...
OTHERWISE VFR.
FRIDAY...SLGT CHC SHRA. OTHERWISE VFR.
SATURDAY...VFR.
MDB
&&
.MARINE...
302 PM CDT
HIGH PRESSURE STRECHES ACROSS THE EASTERN HALF OF THE US. THE WEAK
PRESSURE GRADIENT HAS CREATED LIGHT WINDS ACROSS THE AREA...WITH
THE STRONGEST WINDS IN THE NORTHERN HALF OF LAKE MICHIGAN. WEAK
FLOW WILL CONTINUE OVERNIGHT. A LOW PRESSURE SYSTEM WILL PASS TO
OUR WEST TOMORROW...TIGHTENING THE PRESSURE GRADIENT AND CREATING
STRONGER SOUTHEAST WINDS. A NEW AREA OF LOW PRESSURE WILL DEVELOP
OVER THE GREAT PLAINS TUESDAY AND MOVE EAST. THE LOW AND A COLD
FRONT WILL PASS THROUGH LAKE MICHIGAN ON THURSDAY. MODELS
INDICATE A BROAD TROUGH WILL BE CENTERED OVER THE WESTERN GREAT
LAKES ON THURSDAY. WINDS UNDER THE TROUGH AXIS WILL BE RELATIVELY
WEAKER THAN IN SURROUNDING AREAS. BEHIND THE FRONT...COLD AIR WILL
CREATE UNSTABLE CONDITIONS OVER THE LAKE WITH GALES UP TO 35 KT
OVER THE SOUTHERN HALF OF LAKE MICHIGAN...AND WINDS UP TO 30 KT
OVER THE NORTHERN HALF OF LAKE MICHIGAN. WINDS BEGIN TO WEAKEN
FRIDAY NIGHT.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
