303 PM CDT
QUIET AND DRY WEATHER WILL PERSIST THROUGH THE WEEK AND INTO NEXT
WEEKEND WITH A SLOW BUT STEADY WARMING TREND COMMENCING. AFTERNOON
WATER VAPOR IMAGERY SHOWS A VERY AMPLIFIED PATTERN ACROSS NORTH
AMERICA AND THE ADJACENT AREAS OF THE ATLANTIC AND PACIFIC.
HURRICANE OPHELIA CONTINUES TO RACE NORTH AND NORTHEASTWARD OFF THE
NEWFOUNDLAND COAST WHILE A LARGE CUTOFF UPPER LOW SPINS OVER THE
MID-ATLANTIC STATES. HIGH AMPLITUDE AND EXPANSIVE UPPER RIDGING IS
POSITIONED OVER THE CENTER OF THE CONUS AND IS VERY SLOWLY DRIFTING
EASTWARD AS A DEEP UPPER TROUGH PUSHES TOWARD THE WEST COAST. AT THE
SURFACE...HIGH PRESSURE EXTENDS FROM NORTHERN LAKE MICHIGAN
SOUTHWARD INTO THE DEEP SOUTH.
THE SHORT TERM CONCERN IS LOW TEMPERATURES TONIGHT. THE CENTER OF
THE HIGH WILL BE SOUTH OF THE AREA BUT THE BROAD RIDGE AXIS WILL
REMAIN OVERHEAD TONIGHT. THIS WILL ALLOW WINDS TO DROP OFF ACROSS
THE AREA...ESPECIALLY WEST WHICH WILL COMBINE WITH CLEAR TO MOSTLY
CLEAR SKIES TO ALLOW FOR DECENT RADIATIONAL COOLING. GUIDANCE
APPEARS TO BE TOO WARM FOR MOST OF THE AREA WITH LOWEST TEMPS OF
AROUND 40. GIVEN THE RADIATIONAL SET UP AND THE FACT THAT DEW POINTS
HAVE MIXED OUT TO THE LOW 30S OR LOWER FOR MANY AREAS HAVE OPTED
TO LOWER OVERNIGHT TEMPS WEST AND SOUTH OUTSIDE OF THE CHICAGO
METRO. THUS EXPECT MID/UPPER 30S WEST AND UPPER 30S SOUTH. STILL
HAVE CONCERNS THAT THIS MAY NOT BE COOL ENOUGH BUT WITH POTENTIAL
FOR A VERY LIGHT BREEZE EVEN UNDER THE RIDGE AND SOME PERIODIC THIN
CIRRUS WILL HOLD OFF FROM GOING MUCH LOWER FOR NOW. WILL INCLUDE
PATCHY FROST ACROSS AREAS OUTSIDE THE MOST DENSE URBAN AREAS AND
CLOSE TO LAKE MICHIGAN.
THE WEST COAST TROUGH WILL CONTINUE TO MAKE EASTWARD PROGRESS OVER
THE NEXT DAY OR TWO WHICH WILL HELP TO AMPLIFY THE RIDGE ACROSS THE
MIDDLE OF THE COUNTRY. THE EASTERN TROUGH WILL REMAIN ENTRENCHED
OVER THE MID-ATLANTIC/NEW ENGLAND. ULTIMATELY...THE PATTERN IS
EVOLVING INTO AN OMEGA BLOCK WHICH TRANSLATES TO SLOW CHANGES IN THE
UPPER FLOW OVERHEAD AND TRANQUIL WEATHER THROUGH THE WEEK. THE UPPER
RIDGE AXIS WILL MOVE EAST AND THEN REFORM TO THE WEST AS ENERGY
MOVES ACROSS ITS NORTHERN FLANK ACROSS CENTRAL CANADA AND WAVES
EJECT FROM THE WESTERN TROUGH WHICH WILL BE WORKING INTO THE FOUR
CORNERS REGION. THE BLOCK WILL BECOME BETTER ORGANIZED BY LATE WEEK
AS A MORE SIGNIFICANT UPPER TROUGH MOVES ONSHORE OVER CALIFORNIA AND
CUTS OFF OVER THE FOUR CORNERS.
AS A RESULT...DRY WEATHER IS EXPECTED THROUGH AT LEAST THE END OF
THE WEEK. THE SLOW PROGRESSION OF THE SYSTEM WILL MEAN A SLOW BUT
STEADY WARMING TREND AS THE SURFACE HIGH MOVES EAST AND LIGHT
SOUTHERLY FLOW RETURNS. HIGHS WILL BE RETURNING TO THE 70S FOR
WESTERN AND SOUTHERN AREAS OF THE CWA MONDAY WITH LOW TO MID 70S
FOR ALL AREAS TUESDAY. HIGHS WILL REMAIN IN THE 70S INTO THE
WEEKEND. ONE POTENTIAL FLY IN THE OINTMENT COULD BE
TUESDAY/WEDNESDAY AS THE WAVES FROM THE BUILDING WESTERN TROUGH MOVE
ALONG THE WESTERN AND NORTHERN PERIPHERY OF THE UPPER RIDGE. ITS
POSSIBLE...ALTHOUGH UNLIKELY...THAT ONE OF THESE WAVES COULD MOVE
CLOSE TO THE AREA AND BRING SOME INCREASED CLOUD COVER BUT LITTLE
MORE THAN THAT WITH A DRY LOWER ATMOSPHERE REMAINING IN PLACE. NEXT
WEEKEND LOOKS TO REMAIN DRY AS WELL WITH THE BLOCKING PATTERN
EXPECTED TO PROGRESS VERY SLOWLY KEEPING ANY PRECIP PRODUCING SYSTEM
TO THE WEST. IT DOES APPEAR THE BLOCK WILL TRY TO BREAK DOWN LATER
IN THE WEEKEND WHICH MAY RESULT IN A FRONTAL PASSAGE VERY LATE IN
THE WEEKEND OR MORE LIKELY EARLY NEXT WEEK.
MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* NO SIGNIFICANT CONCERNS.
BMD
//DISCUSSION...UPDATED 18Z...
VERY QUIET WEATHER FORECAST AS HIGH PRESSURE CENTERED JUST WEST OF
THE FORECAST AREA THIS AFTERNOON WILL CONTINUE TO PROVIDE A LIGHT
NORTH/NORTHWESTERLY FLOW THROUGH THE REMAINDER OF THE DAY. WINDS
WILL BE SOMEWHAT VARIABLE...RANGING FROM ROUGHLY 290-020...BUT
SHOULD PREDOMINATELY BE OUT OF THE NNW. SKIES WILL REMAIN MOSTLY
CLEAR THROUGH THE PERIOD. OVERNIGHT...WINDS ARE EXPECTED TO
DIMINISH...AND MAY GO CALM FOR A PERIOD IN THE EARLY MORNING HOURS
MONDAY. MODELS SUGGEST THE HIGH MAY REORIENT ITSELF FARTHER TO THE
NORTH ON MONDAY...ALLOWING WINDS TO TURN MORE TO THE
NORTHEAST MONDAY AFTERNOON...HOWEVER SPEEDS WILL CONTINUE TO BE
RELATIVELY LIGHT...LESS THAN 10 KT. BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT THROUGH SATURDAY...VFR.
BEACHLER
&&
.MARINE...
237 PM CDT
HIGH PRESSURE HAS MOVED ACROSS THE MID MISSISSIPPI VALLEY AND
WESTERN GREAT LAKES THIS AFTERNOON...ALLOWING WINDS TO CONTINUE TO
SUBSIDE. SOME WINDS OCCASIONALLY IN THE 10 TO 20 KT RANGE ARE
POSSIBLE THIS AFTERNOON AT THE FAR SOUTH/SOUTHEASTERN PORTION OF
LAKE MICHIGAN...BUT OTHERWISE WINDS 15 KTS OR LESS ARE EXPECTED
THROUGH THE REST OF THE WEEKEND AND FIRST HALF OF NEXT WEEK. THE
HIGH WILL SHIFT EAST OF LAKE MICHIGAN LATE TUESDAY ALLOWING WINDS TO
SHIFT TO THE SOUTH. SOUTHERLY WINDS MAY INCREASE BACK INTO THE 10 TO
20 KT RANGE FOR NORTHERN LAKE MICHIGAN FOR A PERIOD LATE WEDNESDAY
THROUGH FRIDAY...BUT NO SIGNIFICANT WINDS OR WEATHER SYSTEMS ARE
FORECAST THROUGH THE REMAINDER OF THE WEEK AS THE HIGH PRESSURE
AMPLIFIES AND REMAINS ANCHORED ACROSS THE REGION. BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
