820
FXUS63 KIWX 221047
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
547 AM EST SAT FEB 22 2025
KEY MESSAGES
- A MODERATING TEMPERATURE TREND THIS WEEKEND WITH HIGH
TEMPERATURES IN THE 40S AND LOW 50S BY MONDAY AND TUESDAY.
- A FEW SYSTEMS TO BRING CHANCES OF SOME LIGHT RAIN MONDAY NIGHT
NIGHT THROUGH WEDNESDAY.
- TEMPERATURES COOLING BACK TO NEAR SEASONABLE LEVELS THURSDAY
AND FRIDAY WITH ANOTHER POTENTIAL SYSTEM BRINGING A CHANCE OF
SNOW SHOWERS.
DISCUSSION
ISSUED AT 340 AM EST SAT FEB 22 2025
DRY CONDITIONS ARE EXPECTED THIS WEEKEND WITH A SHARP MODERATING
TREND HEADED INTO EARLY NEXT WEEK.
A BROAD NORTHWEST UPPER FLOW PATTERN WILL ALLOW A SERIES OF MOISTURE
STARVED WEAK SHORT WAVES TO TRACK ACROSS THE REGION THROUGH SUNDAY
NIGHT. ONE OF THESE SHORT WAVES THIS MORNING IS TRACKING ACROSS
ARROWHEAD OF MN/SOUTHERN MANITOBA. NORTHERN PORTIONS OF THE
FORECAST AREA WILL LIKELY BE GRAZED BY HIGH CLOUD DECK WITH
THIS SHORT WAVE TOWARD MIDDAY BEFORE CLEARING OUT. ANOTHER
POSITIVELY TILTED SHORT WAVE IS LOCATED OVER THE CENTRAL PLAINS
AND WILL TRACK ACROSS THE LOWER OHIO VALLEY THIS AFTERNOON. THE
LOW LEVEL AIRMASS DOWNSTREAM OF BOTH OF THESE SHORT WAVES IS
EXTREMELY DRY AS EVIDENT BY 0.11 PWAT SAMPLED FROM 00Z KDVN RAOB
LAST EVENING. THE MAIN SENSIBLE WEATHER IMPACT FROM THE
SOUTHERN STREAM SHORT WAVE TODAY WILL BE TO KEEP A NEAR NEUTRAL
TEMPERATURE ADVECTION PATTERN IN PLACE DESPITE STRENGTHENING
SOUTHWESTERLY FLOW TODAY. WHILE THERMAL ADVECTION IS WEAK TODAY,
CONTINUED MODIFICATION OF LOW LEVEL AIRMASS SHOULD SUPPORT
HIGHS A FEW DEGREES WARMER THAN YESTERDAY FOR MOST LOCATIONS.
HIGHS IN THE LOW-MID 30S STILL APPEAR REASONABLE, PERHAPS A BIT
COOLER FOR AREAS WITH LINGERING DEEPER SNOWPACK RECEIVED FROM
THE RECENT LAKE EFFECT SNOW. ANOTHER POCKET OF SLIGHTLY GREATER
SNOW DEPTH LIKELY PERSISTS JUST SOUTH OF KFWA VICINITY INTO
PORTIONS OF NW OHIO. WARMEST TEMPS LIKELY TO OCCUR ACROSS WEST
CENTRAL INTO PORTIONS OF NORTHWEST INDIANA AS SOUTHWEST FLOW
TRAJECTORIES WILL NOT BE ASSOCIATED WITH MUCH UPSTREAM SNOWPACK.
NEAR TERM FORECAST SOUNDINGS SUGGEST DECENT MIXING UP TO
2000-2500 FEET TODAY, WHICH WOULD SUPPORT SOUTHWEST GUSTS TO 20
TO 25 MPH.
FOR TONIGHT, DEPARTURE OF THESE WEAK UPPER LEVEL SHORT WAVES WILL
ALLOW FOR BACKING OF LOW LEVEL FLOW AND STRONGER LOW LEVEL WARM
ADVECTION DEVELOPING INTO SUNDAY. ADDITIONAL EASTERN PACIFIC SMALL
SCALE WAVES WILL TAKE A TRACK NORTH OF THE LOCAL AREA SUNDAY AND
SUNDAY NIGHT WITH UPSTREAM PACIFIC MOISTURE ALSO BYPASSING TO THE
NORTH. THIS SHOULD PROVIDE JUST THICKENING MID/HIGH CLOUDS FOR
SUNDAY. EVEN WITH THE CLOUD COVER AND MORE LIMITED MIXED LAYER
DEPTHS SUNDAY, HIGHS WILL BE NOTICEABLY WARMER FOR SUNDAY AFTERNOON
INTO THE 35 TO 40 DEGREE RANGE. THE STRONGEST OF THESE EASTERN
PACIFIC SHORT WAVE TROUGHS IS EXPECTED TO INTERACT WITH EASTERN
PACIFIC JET AND AMPLIFY ACROSS SOUTH CENTRAL CANADA SUNDAY NIGHT
INTO MONDAY MORNING. THIS WILL CONTINUE TO KEEP PRECIP CHANCES
CONFINED WELL NORTH OF THE LOCAL AREA INTO MONDAY AFTERNOON.
THE PARADE OF EASTERN PACIFIC WAVES CONTINUES FOR TUESDAY THROUGH
THURSDAY. FORECAST DETAILS IN TERMS OF POPS STILL DIFFICULT TO
NARROW DOWN FOR MONDAY NIGHT/TUESDAY AS THE STRENGTH/TRACK OF HIGHLY
PROGRESSIVE SMALL SCALE WAVES AND ANY ASSOCIATED TIGHTER LOW
LEVEL BAROCLINIC RIBBON DIFFICULT TO RESOLVE AT THIS FORECAST
DISTANCE. THUS, WILL MAINTAIN JUST SOME LOW-MID RANGE CHANCE
RAIN POPS FOR THIS PERIOD. OF HIGHER CONFIDENCE IS THE BROAD
WEST-NORTHWEST MID/UPPER FLOW PATTERN OFFERING CONTINUED
MODERATION OF TEMPERATURES INTO MIDWEEK WITH HIGHS IN THE 40S TO
LOWER 50S FOR MONDAY THROUGH WEDNESDAY.
THE BEST CHANCES OF PRECIP IN THE LONG TERM PERIOD STILL LOOK
POSSIBLE FOR THE WEDNESDAY-THURSDAY PERIOD AS PACIFIC WAVES TAKE
A PROGRESSIVELY MORE SOUTHWARD TRACK GIVEN GRADUAL FLOW
AMPLIFICATION AND AMPLIFICATION OF UPSTREAM WESTERN CONUS UPPER
RIDGE. MEDIUM RANGE GUIDANCE STILL DEPICTS A CONTINUED
DISJOINTED, UNPHASED APPEARANCE TO THE SHORT WAVE TROUGH
EVOLUTION. AFTER ANOTHER MIDWEEK LIGHT RAIN CHANCE, A DIGGING
WAVE IN NORTHWEST UPPER FLOW MAY BE ACCOMPANIED BY SOME BETTER
FRONTAL FORCING WITH A POSSIBLE INTRUSION OF COLDER AIR INTO THE
GREAT LAKES FOR LATE WEEK/EARLY NEXT WEEKEND. WILL CONTINUE TO
HANDLE THIS WITH LOW TO MID RANGE CHANCE SNOW POPS FOR
THURSDAY/FRIDAY AS TEMPS COOL TO NEAR NORMAL FOR LATE FEBRUARY.
AVIATION /12Z TAFS THROUGH 12Z SUNDAY/
ISSUED AT 546 AM EST SAT FEB 22 2025
HIGH PRESSURE AND A VERY DRY AIRMASS WILL REMAIN OVER THE REGION
AND KEEP VFR CONDITIONS. WINDS SHOULD REMAIN UNDER 10 KNOTS.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...NONE.
DISCUSSION...MARSILI
AVIATION...SKIPPER
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