773
FXUS63 KIND 290458
AFDIND
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1258 AM EDT SAT MAR 29 2025
KEY MESSAGES
- MUCH WARMER TEMPERATURES INTO THE WEEKEND
- WET AND UNSETTLED PATTERN DEVELOPING WITH PERIODIC RAIN AND STORM
CHANCES THROUGH MONDAY
- STRONG TO SEVERE STORMS EXPECTED SUNDAY AFTERNOON AND EVENING
FORECAST UPDATE
ISSUED AT 959 PM EDT FRI MAR 28 2025
CENTRAL INDIANA WILL REMAIN WITHIN A SLOWLY APPROACHING SYNOPTIC
SYSTEM'S WARM SECTOR OVERNIGHT...AND THE ACCOMPANYING MODERATE
SURFACE GRADIENT ALIGNED BETWEEN THE TROUGH STRETCHED FROM THE
KANSAS HIGH PLAINS TO MINNEAPOLIS AND BROAD SURFACE RIDGE TO THE
SOUTHEAST. WHILE FLOW HAS DECREASED SLIGHTLY SINCE FRIDAY'S GUSTY
PRESENCE...SOUTH-SOUTHWESTERLY WINDS WILL BE SUSTAINED AT 10-15 MPH
WITH GUSTS STILL REACHING 20-25 MPH THROUGH DAYBREAK.
A PIECE OF SOUTHERN STREAM ENERGY OVER THE LOWER MISSISSIPPI VALLEY
WILL DIRECT WESTERN GULF MOISTURE NORTHWARD INTO THE LOCAL REGION BY
DAWN WITH PATCHY DRIZZLE AND A FEW WIDELY SCATTERED SHOWERS REACHING
AREA NEAR AND SOUTH OF TERRE HAUTE BY 12Z SATURDAY. THE WARM
ADVECTIVE FLOW WILL ONLY ALLOW READINGS TO DROP ANOTHER 10 DEGREES
OR SO...PROVIDING ANOTHER PERIOD OF NEAR-RECORD TEMPERATURES
DROPPING TO ONLY THE LOW 60S.
SHORT TERM (THIS EVENING THROUGH SATURDAY)
ISSUED AT 301 PM EDT FRI MAR 28 2025
TODAY AND TONIGHT
SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE TO DIMINISH ACROSS THE
AREA AS A WARM FRONT LIFTS NORTHWARD INTO NORTHERN INDIANA. NOW THAT
WE'RE ON THE WARM SIDE OF THE FRONT, WINDS ARE SWITCHING FROM SE TO
S BEFORE EVENTUALLY BECOMING SW. SKIES ARE ALSO BEGINNING TO CLEAR,
AND SATELLITE IMAGERY SHOWS ADDITIONAL UPSTREAM CLEARING.
SHORT TERM MODEL GUIDANCE SHOWS A TIGHT MSLP GRADIENT DEVELOPING BY
THIS AFTERNOON, LEADING TO STRONG WIND GUSTS AS BOUNDARY LAYER
MIXING DEEPENS. WIND GUSTS ARE THE PRIMARY FORECAST CHALLENGE TODAY
AS VALUES CLOSE TO 40-45MPH ARE POSSIBLE WHICH IS RIGHT NEAR
ADVISORY LEVEL. FOR NOW, HIGH-RES GUIDANCE DOES NOT INDICATE THAT A
LARGE PORTION OF OUR AREA WILL EXCEED THE 45MPH THRESHOLD FOR LONG
ENOUGH, AND WE WILL CARRY AN SPS TO HIGHLIGHT GUST POTENTIAL FOR
NOW.
STRONG SOUTHWESTERLY FLOW, CLEARING SKIES, AND WARM AIR ADVECTION
WILL LEAD TO A MUCH WARMER DAY TODAY COMPARED TO YESTERDAY. IN FACT,
TEMPERATURES MAY BE AS MUCH AS 20 DEGREES WARMER WITH HIGHS NEAR 80
DEGREES POSSIBLE ACROSS OUR SOUTHWEST. ELSEWHERE, MID TO UPPER 70S
ARE EXPECTED. TEMPERATURES DECREASE OVERNIGHT BUT ONLY INTO THE LOW
60S AS WINDS REMAIN ELEVATED AND WARM AIR ADVECTION CONTINUES.
SATURDAY
A CUT OFF UPPER-WAVE CURRENTLY LOCATED OVER TEXAS WILL LIFT
NORTHWARD AHEAD OF A TROUGH EMERGING FROM THE ROCKIES. THIS FEATURE
WILL ALLOW DEEPER MOISTURE TO ADVECT NORTHWARD ALONG WITH THE WARMER
AIR MASS. STRONG MOISTURE ADVECTION ALONG WITH ENHANCED FORCING FROM
THE UPPER WAVE AND ADVANCING TROUGH SHOULD LEAD TO AN AREA OF
SHOWERS AND STORMS DURING THE DAY SATURDAY. WIDESPREAD CLOUDS AND
RAIN WILL LIKELY KEEP TEMPERATURES DOWN COMPARED TO TODAY, WITH
HIGHS IN THE LOW 70S. RAINFALL COULD BE LOCALLY HEAVY WITH AMOUNTS
AS HIGH AS 1 INCH POSSIBLE.
LONG TERM (SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 301 PM EDT FRI MAR 28 2025
ALL EYES ARE ON A POTENTIAL SEVERE WEATHER OUTBREAK DURING THE
SUNDAY TO SUNDAY NIGHT TIMEFRAME.
SYNOPTIC OVERVIEW
A BROAD TROUGH IS CURRENTLY MOVING ONSHORE OVER THE WEST COAST AND
SHOULD EMERGE INTO THE PLAINS BY SATURDAY AFTERNOON. AN EMBEDDED
SHORTWAVE WITHIN THE BROADER TROUGH SWINGS AROUND AND REACHES
INDIANA BY SUNDAY AFTERNOON. CYCLOGENESIS AT THE SURFACE COMBINED
WITH WARM MOIST ADVECTION WILL SET THE STAGE FOR THUNDERSTORM
DEVELOPMENT THAT AFTERNOON AND INTO SUNDAY NIGHT.
GUIDANCE HAS BEEN TRENDING TOWARDS A SLIGHTLY STRONGER SURFACE LOW,
WHICH LOOKS TO BE SITUATED OVER THE CHICAGO AREA EARLY ON SUNDAY. A
STRONGER MODELED LOW HAS RESULTED IN WHAT INITIALLY LOOKED LIKE
SOUTHWESTERLY SURFACE FLOW BECOMING MORE SOUTHERLY IN NATURE. THIS
HAS RESULTED IN HODOGRAPHS THAT SHOW MORE CURVATURE IN THE LOWER
LEVELS. AS SUCH, THE THREAT FOR TORNADOES IS INCREASING ACROSS THE
REGION.
SEVERE WEATHER DETAILS
AS MENTIONED ABOVE, TORNADOES ARE A POTENTIAL HAZARD AS GREATER
TURNING OF WIND WITH HEIGHT IS NOW SHONE IN MODEL GUIDANCE.
ADDITIONALLY, VERY RICH LOW-LEVEL MOISTURE IS SHOWN BY NEARLY ALL
GUIDANCE (DEW POINTS INTO THE LOW 60S) ALONG WITH MODEST TO STEEP
NEAR-SURFACE LAPSE RATES. TORNADO POTENTIAL MAY BE LIMITED AT LEAST
TEMPORALLY AS UPSCALE GROWTH MAY OCCUR QUICKLY DUE TO SHEAR VECTORS
ROUGHLY ALIGNED WITH THE INITIATING BOUNDARY.
ADDITIONALLY, STEEP LAPSE RATES THROUGH THE COLUMN (7.0 TO 7.5 C/KM)
AND HIGH BULK SHEAR (OVER 50KT) WILL COMBINE WITH TALL CAPE PROFILES
TO ALLOW FOR LARGE HAIL. STRONG DAMAGING WINDS ARE ALSO A HAZARD AS
FAST WIND SPEEDS ASSOCIATED WITH A LOW-LEVEL JET COULD EASILY BE
MIXED DOWNWARD BY ANY THUNDERSTORM GIVEN THE STEEP LAPSE RATES.
FLASH FLOODING MAY ALSO BE POSSIBLE GIVEN RICH MOISTURE AND
POTENTIALLY TRAINING STORM SITUATIONS.
AS FOR TIMING, GUIDANCE STILL VARIES SOMEWHAT BUT A ROUGH CONSENSUS
OF SUNDAY AFTERNOON INTO SUNDAY NIGHT IS NOW TAKING SHAPE.
CONVECTIVE DEVELOPMENT AND TIMING COULD BE A BIT MORE UNCERTAIN THAN
NORMAL DUE TO THE PRESENCE OF MORNING CONVECTION, WHICH MAY ALTER
THE ENVIRONMENT ENOUGH TO HAMPER GUIDANCE. SINCE GUIDANCE IS STILL
IN THE PROCESS OF TRENDING TOWARDS A STRONGER SURFACE LOW (A TREND
THAT COULD JUST AS EASILY REVERSE), CONFIDENCE IS STILL ONLY
MODERATE REGARDING CONVECTIVE COVERAGE AND TIMING. CONFIDENCE WILL
INCREASE WITH TIME AS GUIDANCE HONES IN ON HOW THE VARIOUS FEATURES
EVOLVE THROUGH THE DAY TOMORROW.
MONDAY ONWARD
ENSEMBLE GUIDANCE IS HINTING AT YET ANOTHER TROUGH DIGGING INTO THE
PLAINS BY ABOUT MIDWEEK NEXT WEEK. SIGNIFICANT VARIATION EXISTS
AMONG VARIOUS DETERMINISTIC GUIDANCE, SO LITTLE CAN BE SAID ABOUT
PARTICULAR THREATS AND DETAILS AT THIS POINT. HOWEVER, GIVEN THE
PLACEMENT OF THE TROUGH AND SIGNALS WITHIN ENSEMBLE GUIDANCE...WE
CAN SAY THAT THUNDERSTORMS, POSSIBLY STRONG TO SEVERE, ARE ONCE
AGAIN POSSIBLE. ADDITIONALLY, ENSEMBLES ARE SHOWING A SIGNAL FOR
HEAVY PRECIPITATION WITH ASSOCIATED FLOODING / RIVER FLOODING
POTENTIAL. STAY TUNED FOR DETAILS AS A MODEL CONSENSUS EMERGES IN
THE COMING DAYS.
OVERALL, THE UPCOMING LONG RANGE PATTERN LOOKS ACTIVE AND WET, ALONG
WITH NEAR TO ABOVE-AVERAGE TEMPERATURES.
AVIATION (06Z TAF ISSUANCE)
ISSUED AT 1258 AM EDT SAT MAR 29 2025
IMPACTS:
- SOME WIND GUSTS UP TO AROUND 20KT OVERNIGHT
- SOME NON-CONVECTIVE LLWS AT TIMES INTO SATURDAY MORNING
- MVFR CEILINGS ARRIVING AFTER 22Z SATURDAY FROM WEST TO EAST
- SCATTERED TO NUMEROUS SHOWERS DEVELOPING SATURDAY
DISCUSSION:
VFR CONDITIONS WILL CONTINUE THROUGH MUCH OF THE DAY SATURDAY,
BEFORE MORE WIDESPREAD MVFR CONDITIONS MOVE IN FROM THE WEST.
SCATTERED TO NUMEROUS SHOWERS SATURDAY INTO SATURDAY EVENING COULD
PRODUCE BRIEF MVFR CEILINGS IN THE HEAVIER SHOWERS.
WIND GUSTS LOOK TO BE SPORADIC OVERNIGHT AND UP TO AROUND 20KT.
STRONG WINDS NOT FAR OFF THE SURFACE WILL CREATE NON-CONVECTIVE LLWS
CONDITIONS AT TIMES THROUGH AROUND 12Z. WIND GUSTS UP TO AROUND 25KT
WILL OCCUR DURING THE DAYTIME SATURDAY.
IND WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...AGM
SHORT TERM...ECKHOFF
LONG TERM...ECKHOFF
AVIATION...50
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