310 AM CDT
ANOTHER QUIET DAY IS ON TAP FOR THE AREA. A GLANCE AT REGIONAL WATER
VAPOR IMAGERY SHOWS UPPER LEVEL RIDGING AND THE OMEGA BLOCK THAT
HAS BEEN THE DOMINATING INFLUENCE OF RECENT...SLOWLY SHIFTING EAST
AND DAMPENING. LIFTING OUT OF THE NORTHERN PLAINS AND INTO
MANITOBA IS A POTENT SURFACE LOW WITH A FRONT DRAPED SOUTH THROUGH
THE SOUTHERN PLAINS. LOCALLY...SURFACE HIGH PRESSURE CONTINUES TO
SHIFT EAST AND ACROSS THE OHIO VALLEY. SURFACE PRESSURE GRADIENT
WILL STILL BE ALIGNED FROM THE SOUTH AND WINDS WILL REMAIN THAT
WAY THROUGH THE DAY. THE FORECAST REMAINS PRIMARILY UNCHANGED FROM
YESTERDAY...BUT TEMPERATURES ALOFT WILL COOL SLIGHTLY AND HIGHS
SHOULD BE JUST SHY OF HOW WARM THEY WERE FRIDAY AFTERNOON WITH MID
80S ACROSS THE SOUTHWEST AND LOWER 80S CLOSER TO THE CHICAGO METRO.
DEWPOINTS SHOULD MIX OUT SOME THIS AFTERNOON...SIMILAR TO FRIDAY
DESPITE WEAK MOISTURE ADVECTION. FORECAST SOUNDINGS HIGHLIGHT DEEP
MIXING AOA 875 HPA INTO THE PEAK OF THE AFTERNOON... AND THAT
SHOULD HELP TO YIELD LOWER 50S DEWPOINTS ACROSS MUCH OF THE
WESTERN COUNTIES IN THE CWA...WITH DEWPOINTS DIPPING INTO THE MID
50S FOR AREAS CLOSE TO THE LAKE.
WITH THE SLOWLY COOLING MID LEVELS THROUGH THE WEEKEND...HIGHS
WILL BEGIN TREND DOWN THROUGH THE WEEK BUT WILL STILL REMAIN WELL
ABOVE NORMAL. THE SECOND WEEK OF OCTOBER GENERALLY SEES HIGHS IN
THE MIDDLE 60S WITH OVERNIGHT LOWS IN THE MIDDLE 40S. WE LIKELY
WONT RETURN TO NORMAL UNTIL THURSDAY...WITH HIGHS TRENDING THROUGH
THE 70S TO THAT POINT. RAIN STILL LOOKS TO BE HELD OFF UNTIL THE
MIDDLE OF THE WEEK AS THE UPPER LEVEL RIDGE BEGINS TO FLATTEN OUT
AND ANOTHER WAVE LIFTS NORTH AND INTO CANADA. MODELS ARE IN PRETTY
GOOD AGREEMENT AT THIS RANGE WITH SLOWLY BRINGING A FRONT THROUGH
THE REGION OVERNIGHT TUESDAY AND INTO WEDNESDAY. INTO THE LONGER
RANGE...THE FRONT WILL PUSH THROUGH BUT AN UPPER LEVEL LOW WILL
SLOWLY MEANDER SOUTH AND ACROSS THE WESTERN GREAT LAKES BEHIND
IT...AND LINGER THROUGH THE END OF THE WEEK...BRINGING OFF AND ON
CHANCES THROUGH THAT TIME. THE RELATIVE MEASURE OF PREDICTABILITY
/RMOP/ REALLY FALLS OFF THE BOARD AS THE UPPER LOW SPINS
OVERHEAD /GENERALLY F120 AND BEYOND/...AND WILL HAVE TO RUN CHANCE
SHOWERS BEYOND THE FROPA AND THROUGH THE END OF THE WEEK...THOUGH
THERE WILL BE MORE HOURS OF NO RAIN VS RAIN. UNDER THE COOL
NORTHWEST FLOW...TEMPERATURES WILL AGAIN RETURN TO NON NORMAL
STATUS...JUST IN THE OPPOSITE DIRECTION WILL LIKELY STRUGGLE TO
REACH 60 BY THE END OF THE WEEK.
SHEA
&&
.FIRE WEATHER...
310 AM CDT
HIGH PRESSURE AND DRY CONDITIONS WILL CONTINUE TO BE THE DOMINATING
FEATURE THROUGH THE EARLY PART OF THE NEXT WORK WEEK. FOR
TODAY...WINDS WILL AGAIN INCREASE AND GUST NEAR THE 20 KT RANGE FOR
AREAS WEST OF I-39...WITH SLIGHTLY LOWER GUSTS FOR EAST. DEEP
MIXING WILL ALLOW DRY DEWPOINTS TO WORK THEIR WAY DOWN TO THE
SURFACE AND AROUND 50 DEGREES...AND EXPECT RH VALUES TO FALL
AGAIN IN RESPONSE...LIKELY DIPPING INTO THE LOW 30% RANGE INTO THE
AFTERNOON AWAY FROM THE LAKE. WINDS WILL CONTINUE TO SLACKEN INTO
THE EVENING AND THERE WILL BE RECOVERY OVERNIGHT. MOISTURE WILL
SLOWLY BE ON THE INCREASE BUT SIMILAR CONDITIONS MAY BE EXPECTED
ACROSS THE SOUTHWESTERN COUNTIES AGAIN ON SUNDAY. THE UNSEASONABLY
WARM WEATHER WILL CONTINUE THROUGH MONDAY.
SHEA
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SOMEWHAT VARIABLE AND GUSTY WINDS THIS AFTERNOON. DIRECTION FROM
170 TO 220...WITH OCCASIONAL GUSTS INTO THE UPPER TEENS.
LENNING
//DISCUSSION...UPDATED 18Z...
EXPECTING A VERY GRADUAL BACKING OF WINDS FROM SOUTHWEST TO
SOUTHEAST THROUGH THE NEXT 24 HOURS...AND THEN TO EAST BY TOMORROW
EVENING. LAKE BREEZE INFLUENCES THIS AFTERNOON ARE WORKING TO KEEP
THE WINDS SLIGHTLY MORE SOUTH THAN THEY OTHERWISE MIGHT BE IN THE
PREDOMINANT SOUTHWEST FLOW. OCCASIONAL GUSTS MIXING DOWN ARE THEN
TURNING WINDS BACK TO THE SOUTHWEST FOR BRIEF PERIODS. TRAFFIC
FLOW APPEARS TO BE LIGHT ENOUGH TO WORK AROUND THESE
UNCERTAINTIES. OTHERWISE NO SIGNIFICANT WEATHER TO MENTION FOR THE
FORECAST PERIOD...AND PERHAPS FOR THE FIRST HALF OF NEXT WEEK.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE IN WIND DIRECTION. MEDIUM TO HIGH CONFIDENCE
IN WIND SPEED.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT THROUGH TUESDAY...VFR
WEDNESDAY...VFR WITH MVFR POSSIBLE. CHANCE SHRA/SLIGHT CHANCE
TSRA.
THURSDAY...VFR WITH MVFR POSSIBLE. CHANCE SHRA.
FRIDAY...VFR WITH SLIGHT CHANCE SHRA.
MDB
&&
.MARINE...
213 PM CDT
A PERSISTENT DOME OF HIGH PRESSURE OVER THE EAST COAST...WITH LOW
PRESSURE PARKED ACROSS CENTRAL CANADA...WILL PROVIDE MILD
SOUTHERLY FLOW...OCCASIONALLY VARIABLE BETWEEN SOUTHWEST AND
EAST...OVER THE LAKE THROUGH THE REST OF THE WEEKEND AND INTO THE
FIRST HALF OF NEXT WEEK. TODAY THE LONG SOUTH TO NORTH FETCH OVER
THE LAKE HAS MAINTAINED WAVES IN THE 4 TO 7 FT RANGE ACROSS THE
NORTHERN END OF THE LAKE...BUT OFFSHORE FLOW IN THE SOUTH END IS
KEEPING WAVES VERY LOW IN THE SOUTHERN NEARSHORE...AND ONLY 1 TO 2
FT AT THE SOUTH BUOY THIS AFTERNOON. WAVES MIGHT BE HIGHER EXCEPT
FOR THE STABLE LAYER UNDER THE WARM SOUTHERLY WINDS AND THE
COOLING LAKE SURFACE.
WINDS WILL WEAKEN SOMEWHAT THROUGH THE NEXT FEW DAYS AND ALSO LOSE
THE LONG FETCH...SO WAVES WILL BE SUBSIDING FROM CURRENT LEVELS
AND SHOULD REMAIN MUCH SMALLER THROUGH MIDWEEK. A COLD FRONT
CROSSING THE LAKE WEDNESDAY NIGHT WILL TURN WINDS WEST AND THEN
EVENTUALLY NORTHWEST BY THE END OF THE WEEK. THE GRADIENT ALSO
APPEARS TO TIGHTEN CONSIDERABLY...POSSIBLY BRINGING NORTHWEST
GALES BY NEXT WEEKEND.
LENNING
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
