337 AM CDT
MAIN CONCERNS FOR THE MORNING UPDATE CONTINUE TO BE THE DEVELOPING
HIGH WIND AND HEAVY RAIN EVENT SETTING UP FOR THE NEXT 36 HOURS.
LITTLE CHANGE TO THE GOING FORECAST HAS BEEN NECESSARY AS THE MODELS
HAVE BEEN DEMONSTRATING VERY GOOD CONTINUITY WITH EACH
OTHER...RUN-TO-RUN...AND WITH THE DEVELOPING PATTERN. THE MAIN
ISSUE FOR TONIGHT HAS BEEN TO DECIDE ON WHAT TO DO WITH HEADLINES.
IN A NUTSHELL...HAVE UPGRADED THE HIGH WIND WATCH TO A HIGH WIND
WARNING FOR THE COUNTIES ADJACENT TO LAKE MICHIGAN...WHILE ADDING A
WIND ADVISORY TO THE ADJACENT WESTERN AND SOUTHERN COUNTIES...BUT
NOT AS FAR WEST AS THE I-39 CORRIDOR.
FOR THE REMAINDER OF THE NIGHT AND INTO THE MORNING HOURS...ONE SFC
LOW CONTINUES TO TRACK NWD INTO THE UPPER OHIO VALLEY AS THE
SUB-TROPICAL LOW MOVES ONSHORE FROM THE NERN GLFMEX TO SRN GEORGIA.
THE GUIDANCE REMAINS CONSISTENT ON SLOWLY TRACKING THE MORE NORTHERN
SFC LOW SLOWLY THROUGH OHIO TODAY AND THEN WRAPPING MORE NWWD BACK
INTO NRN INDIANA BY EARLY THURSDAY MORNING. AS THIS OCCURS...THE
SUB-TROPICAL SFC LOW WILL BE ABSORBED INTO THE OTHER LOW...AIDING IN
FURTHER DEEPENING OF A CONSOLIDATED LOW OF 988MB OVER NRN INDIANA.
THE PRESSURE GRADIENT OVER THE AREA IS ALREADY STRENGTHENING RAPIDLY
WITH WINDS IN EXCESS OF 30KT ALREADY OBSERVED OVER SRN LAKE MICHIGAN
AND THE COASTAL AREAS OF NERN IL/NWRN IN. EXPECT THAT WINDS WILL
CONTINUE TO INCREASE THROUGH THE MORNING. THE LATEST MODEL RUNS ARE
IN GOOD AGREEMENT ON ADVERTISING 925MB WINDS OF 50-60KT BY EARLY
THIS AFTERNOON. WITH FAIRLY STEEP LOW LEVEL LAPSE RATES DEVELOPING
TODAY...SEE LITTLE REASON WHY THE STRONG WINDS WILL NOT MIX DOWN TO
THE SURFACE...ESPECIALLY INVOF HEAVIER RAIN SHOWERS. SO...HAVE
UPGRADED THE HIGH WIND WATCH TO A HIGH WIND WARNING. EXPECT THAT
THE STRONGEST WINDS WILL BE LONG THE SHORE OF LAKE MICHIGAN...WITH
WIND SPEEDS DROPPING OFF FARTHER INLAND. WILL ALSO ISSUE A WIND
ADVISORY FOR LOCATIONS OUT TO THE FOX VALLEY AND THE I-55 CORRIDOR.
STRONG WINDS WILL CONTINUE THROUGH TONIGHT. THE LOW WILL FINALLY
LIFT OUT TO THE NORTHEAST THURSDAY MORNING. BRISK NORTH TO
NORTHWEST WINDS WILL CONTINUE ACROSS THE AREA THROUGH THE DAY
THURSDAY...BUT SHOULD DECREASE BELOW HEADLINE CRITERIA BY LATE
MORNING. ONE SIGNIFICANT IMPACT OF THE STRONG NORTH WINDS WILL BE
ON THE LAKEFRONT LOCATIONS WHERE STRONG WINDS WILL DRIVE WAVES AS
HIGH AS 20 TO 25 FEET. THIS WILL LEAD TO COASTAL FLOODING...BEACH
EROSION...ESPECIALLY FOR THE NWRN INDIANA LOCATIONS...AND WATER
SPLASHING UP TO ROADWAYS ADJACENT TO THE LAKE...INCLUDING LAKESHORE
DRIVE IN DOWNTOWN CHICAGO.
IN ADDITION TO THE STRONG WINDS...HEAVY RAIN WILL BE A CONCERN.
WITH THE SYSTEM POSSIBLY ABLE TO TAP SOME SUB-TROPICAL
MOISTURE...HAVE INCREASED QPF AMOUNTS OVER THE AREA. WITH PWATS
APPROACHING 1 INCH WRAPPING AROUND THE LOW...EXPECT PERIODS OF HEAVY
RAIN...ESPECIALLY FOR THE ERN PORTIONS OF THE CWA. NOW EXPECTING
PCPN AMOUNTS OF 2 TO 2.5 INCHES OVER NWRN INDIANA...DECREASING TO
0.5 TO 0.75 INCHES ALONG THE I-39 CORRIDOR. GIVEN THAT THE AREA HAS
NOT SEEN A SIGNIFICANT AMOUNT OF PCPN OVER RECENT WEEKS...AREA
RIVERS SHOULD HAVE ADEQUATE CAPACITY TO HANDLE THE RUNOFF.
HOWEVER...WITH THE HEAVIEST RAIN EXPECTED TO FALL OVER NWRN
INDIANA...THE KANKAKEE RIVER WILL NEED TO BE MONITORED FOR POSSIBLE
FLOODING PROBLEMS. ALSO...IF THERE IS ANY CONVECTIVE ENHANCEMENT TO
RAINFALL RATES...LOCATIONS EAST OF THE I-55 CORRIDOR WILL NEED TO BE
MONITORED FOR URBAN AND SMALL STREAM FLOODING PROBLEMS.
AS THE LOW LIFTS OUT ON THURSDAY AND HIGH PRESSURE BUILDS IN FROM
THE NRN PLAINS...COOLER AIR WILL FILTER OVER THE AREA...WITH
TEMPERATURES REMAINING WELL BELOW NORMAL INTO FRIDAY. HIGHS FOR
THURSDAY SHOULD ONLY BE IN THE UPPER 40S TO AROUND 50...WHILE
OVERNIGHT LOWS SHOULD DROP INTO THE LOWER TO MIDDLE 30S BY FRIDAY
MORNING. SOME MODERATION IS EXPECTED FOR THE WEEKEND AS MORE ZONAL
FLOW AND WEAK RIDING SETS UP OVER THE CNTRL CONUS. NO ADDITIONAL
PCPN IS EXPECTED FOR FRIDAY THROUGH SATURDAY NIGHT...WHILE HIGH
TEMPERATURES CLIMB BACK INTO THE UPPER 50S TO AROUND 60.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* CEILINGS LOWERING TO IFR BY LATE AFTERNOON/EARLY EVENING.
* STRONG NORTH TO NORTHEAST WINDS INCREASING THROUGH LATE
AFTERNOON/EARLY EVENING. GUSTS APPROACHING AND POSSIBLY
SURPASSING 40 KT.
* RAIN INTENSITY AND VISIBILITY IMPACTS.
PAW
//DISCUSSION...UPDATED 12Z...
A STRONG FALL STORM WILL IMPACT THE REGION TODAY BRINGING STRONG
WINDS...PERIODS OF HEAVY RAIN...AND IFR POSSIBLY LIFR CONDITIONS. AN
AREA OF LOW PRESSURE WILL MOVE NORTHWARD FROM THE SOUTHEASTERN CONUS
AND DEEPEN OVER THE UPPER OHIO RIVER VALLEY THIS MORNING. AS THIS
HAPPENS...WINDS WILL INCREASE OUT OF THE NNE/N WITH GUSTS INTO THE
20 TO 30 KT RANGE THIS MORNING INCREASING TO AROUND 40KT BY LATE
THIS AFTERNOON/EARLY THIS EVENING. MEANWHILE...AS DEFORMATION ZONE
PRECIPITATION CONTINUES TO OVERSPREAD THE AREA THIS MORNING AND LOW
PRESSURE MOVES NORTHWEST INTO NORTHERN INDIANA LATER TODAY...EXPECT
CIGS TO CONTINUE TO TREND DOWN. CIGS SHOULD DROP INTO MVFR EARLY
THIS MORNING...AND BY MID AFTERNOON...GUIDANCE IS SUGGESTING CIGS
DROPPING TO OR BELOW 010...WITH MET GUIDANCE EVEN SHOWING LIFR
CONDITIONS AROUND 00Z THIS EVENING. THUS FAR...GUIDANCE HAS BEEN TOO
FAST BRINGING DOWN CIGS AND HAVE HAD TO PUSH BACK TIMING...BUT
DOWNWARD GENERAL TRENDS IN GUIDANCE HAVE BEEN CONSISTENT. EXPECT
CONDITIONS TO REMAIN DOWN THROUGH THE REMAINDER OF THE CURRENT TAF
PERIODS...EXCEPT MAY SEE SOME IMPROVEMENT DURING THE LATE MORNING
INTO THE EARLY AFTERNOON THURSDAY FOR THE END OF THE ORD TAF AS THE
LOW BEGINS TO LIFT AWAY FROM THE REGION. BMD
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM CONFIDENCE IN CEILINGS LOWERING TO IFR...LOW CONFIDENCE
IN TIMING.
* MEDIUM CONFIDENCE IN WIND SPEED...HIGH CONFIDENCE IN DIRECTION.
* LOW CONFIDENCE IN PRECIPITATION AND VISIBILITY TREND.
PAW
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...MVFR POSSIBLE.
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...SLT CHC SHRA.
MONDAY...VFR.
TUESDAY...CHC SHRA.
BMD
&&
.MARINE...
914 AM CDT UPDATE...
...STORM FORCE WINDS STILL EXPECTED ACROSS ALL OF LAKE MICHIGAN BY
LATE AFTERNOON/EARLY THIS EVENING....
FORECAST REMAINS ON TRACK. WINDS ACROSS THE NORTHERN PART OF THE
LAKE HAVE BEEN A LITTLE SLOW TO INCREASE BEYOND 25 KT SO FAR THIS
MORNING BUT EXPECT THEM TO START TO COME UP BY MIDDAY. WINDS ON
THE SOUTH HALF HAVE BEEN STEADILY INCREASING WITH 35-40 KT
REPORTED AT SHORE BASED SITES FROM MICHIGAN CITY WESTWARD AND
NORTHWARD UP THE ILLINOIS SHORE. STRONGER PRESSURE GRADIENT WILL
BE SPREADING NORTHWEST INTO THE AFTERNOON ALLOWING GALES TO SPREAD
ACROSS THE REST OF THE LAKE WITH STORM FORCE WINDS FOLLOWING SUIT.
DID INCREASE WINDS TO 55 KT FOR THE SOUTH HALF OF THE LAKE TONIGHT
AND LOOKING AT THE POTENTIAL FOR 55-60 KT GUSTS FOR A TIME LATE
THIS EVENING AND EARLY TONIGHT.
MDB
FROM 300 AM CDT ISSUANCE
ONLY SIGNIFICANT CHANGE THIS MORNING IS TO UPGRADE THE NORTHERN
THIRD OR SO OF LAKE MICHIGAN FROM A GALE WARNING TO A STORM
WARNING. AN ELONGATED AREA OF LOW PRESSURE EXTENDS FROM SOUTHERN
GEORGIA NORTH INTO SOUTHERN OHIO. THIS LOW WILL CONSOLIDATE DURING
THE DAY AS IT DEEPENS...REACHING NORTHWEST OHIO/FAR NORTHEAST
INDIANA LATE THIS EVENING. A LARGE RIDGE OF HIGH PRESSURE
EXTENDING FROM HUDSON BAY TO TEXAS WILL SLOWLY MOVE EAST TODAY AND
TONIGHT. THE GRADIENT WILL TIGHTEN RAPIDLY BETWEEN THESE TWO
FEATURES THIS AFTERNOON INTO THIS EVENING. SO EXPECTING A PERIOD
OF STEADILY INCREASING GALES FROM NOW THROUGH EARLY
AFTERNOON...FROM SOUTH TO NORTH ACROSS THE LAKE. THEN STORM FORCE
WINDS DEVELOPING BY LATE AFTERNOON ACROSS THE SOUTH...AND
SPREADING NORTH THROUGH THE EVENING. WHILE THE LOW WILL BEGIN TO
WEAKEN AS IT LIFTS NORTHEAST ACROSS THE EASTERN GREAT LAKES
THURSDAY...AND THUS EXPECT STORM FORCE WINDS TO END BY EARLY
THURSDAY AFTERNOON...THE GRADIENT WILL STILL REMAIN QUITE STRONG
AND EXPECT GALES TO PERSIST WELL INTO THURSDAY EVENING BEFORE
FINALLY DIMINISHING TO 30 KTS OR LESS LATE THURSDAY NIGHT. A RIDGE
OF HIGH PRESSURE WILL MOVE ACROSS THE LAKE FRIDAY...WITH A WEAK
TROUGH/COLD FRONT MOVING ACROSS THE WESTERN LAKES SATURDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...HIGH WIND WARNING...ILZ006-ILZ014...3 PM WEDNESDAY TO 10 AM
THURSDAY.
LAKESHORE FLOOD WARNING...ILZ006-ILZ014...3 PM WEDNESDAY TO 4 PM
THURSDAY.
WIND ADVISORY...ILZ005-ILZ012-ILZ013-ILZ020-ILZ021-ILZ022-ILZ023-
ILZ032-ILZ033-ILZ039...3 PM WEDNESDAY TO 10 AM THURSDAY.
IN...HIGH WIND WARNING...INZ001-INZ002...3 PM WEDNESDAY TO 10 AM
THURSDAY.
LAKESHORE FLOOD WARNING...INZ001-INZ002...3 PM WEDNESDAY TO 9 PM
THURSDAY.
WIND ADVISORY...INZ010-INZ011-INZ019...3 PM WEDNESDAY TO 10 AM
THURSDAY.
LM...GALE WARNING...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-
LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM WEDNESDAY.
STORM WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878...3 PM WEDNESDAY TO 3 PM THURSDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565 UNTIL 3
PM WEDNESDAY.
&&
$$
