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 15Z...
* MINOR CONCERNS OVER EXACT WIND DIRECTION AND ONSET TIME OF
GUSTS.
LENNING
//DISCUSSION...UPDATED 12Z...
HIGH PRESSURE CONTINUES TO BE CENTERED OVER THE MID-ATLANTIC
STATES WITH ONE AREA OF LOW PRESSURE MOVING NORTHEAST TOWARD HUDSON
BAY AND ANOTHER WEAKER LOW OVER THE SOUTHERN HIGH PLAINS. WINDS
WILL BE THE MAIN WEATHER ISSUE TODAY. EXPECT WINDS TO FLUCTUATE
BETWEEN SOUTH AND SOUTHWEST AS MIXING INCREASES BY MID MORNING
WITH GUSTS TO AROUND 20 KT DEVELOPING TOWARD RFD AND BETWEEN 15
AND 20KT ACROSS THE CHICAGO METRO AND NORTHWEST INDIANA. THE
GRADIENT WILL SLACKEN LATER THIS AFTERNOON AS THE LOW OVER HUDSON
BAY MOVES FURTHER FROM THE LOCAL AREA WHICH SHOULD HELP TO LIMIT
GUSTS BY MID/LATE AFTERNOON. SPEEDS WILL THEN GRADUALLY DIMINISH
INTO MID EVENING WITH LIGHT WINDS OVERNIGHT AND SUNDAY MORNING.
THE HIGH WILL SHIFT WESTWARD TONIGHT ALLOWING WINDS TO ONLY
MODESTLY INCREASE LATER SUNDAY MORNING. DIRECTION WILL PROBABLY
STILL BE VARIABLE SUNDAY MORNING BUT SHOULD BEGIN TO TAKE A MORE
SOUTHEASTERLY DIRECTION DURING THE DAY SUNDAY. OTHERWISE VFR
CONDITIONS ARE EXPECTED WITH ONLY HIGH CIRRUS MOVING BY AT
TIMES...MAINLY TODAY.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 15Z...
* MEDIUM CONFIDENCE ON WIND DIRECTIONS STAYING ON THE SOUTHERLY
SIDE OF 220 DEGREES...AND GUSTING INTO THE MID TEENS THIS
AFTERNOON.
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...
244 AM CDT
LAKE MICHIGAN LIES IN THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE
OVER THE MID-ATLANTIC STATES AND STRONG LOW PRESSURE OVER EASTERN
MANITOBA. THIS HAS RESULTED IN STRONGER WINDS ACROSS THE NORTHERN
PART OF THE LAKE. STABLE CONDITIONS EXIST IN THE LOWEST FEW HUNDRED
FEET OF THE ATMOSPHERE WITH THE AIRMASS WARMER THAN THE LAKE WATER.
FORTUNATELY THIS IS KEEPING THE MIXING LAYER LIMITED TO THE LOWEST
FEW HUNDRED FEET WITH WINDS JUST ABOVE THAT IN THE 700-900 FT
LEVEL PUSHING 50 KT. EXPECT THAT GUSTS AT LAKE LEVEL WILL BE IN
THE 25-30 KT RANGE ACROSS THE NORTH END OF THE LAKE THROUGH THIS
AFTERNOON. THE TALLEST PILOT HOUSES WILL PROBABLY SEE GUSTS
SLIGHTLY HIGHER...ESPECIALLY THIS MORNING. THE PRESSURE GRADIENT
WILL WEAKEN THIS EVENING AS THE SURFACE LOW PUSHES ACROSS HUDSON
BAY. THIS WILL ALLOW WINDS TO DIMINISH THIS EVENING AND TONIGHT.
HIGH PRESSURE WILL REMAIN CENTERED TO THE EAST BUT EXPAND WESTWARD
ACROSS THE LAKE SUNDAY INTO MONDAY ALLOWING WINDS TO FURTHER DROP
OFF. SPEEDS WILL COME UP AGAIN INTO TUESDAY BUT DO NOT APPEAR TO
BECOME TOO STRONG BUT LOW PRESSURE WILL GRADUALLY APPROACH FROM
THE WEST INTO WEDNESDAY. THIS LOW WILL TAKE ITS TIME MOVING ACROSS
THE REGION BUT A COLD FRONT WILL PASS SOMETIME DURING THE LATTER
PART OF THE WEEK LIKELY ALLOWING UNSTABLE CONDITIONS TO RETURN
OVER THE LAKE SUPPORTING A GOOD POTENTIAL FOR STRONGER GUSTS.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
