Area Forecast Discussion
Issued by NWS Northern Indiana

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KIWX 051118
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
718 AM EDT TUE MAY 5 2015

.SYNOPSIS...
ISSUED AT 152 AM EDT TUE MAY 5 2015

A FRONT WILL MEANDER ACROSS THE AREA THROUGH TODAY...AND BE
ACCOMPANIED BY OCCASIONAL SHOWERS AND ISOLATED TO SCATTERED
THUNDERSTORMS. CLOUD COVER AND RAINFALL WILL KEEP TEMPERATURES IN
THE 60S ACROSS FAR SOUTHERN LOWER MICHIGAN TO THE MID 70S INTO
WEST CENTRAL INDIANA. LOWS TONIGHT WILL FALL BACK INTO THE 50S.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 418 AM EDT TUE MAY 5 2015

HIGH NEAR TERM POPS ESPCLY ACRS WRN CWA AS AMPLE DOWNRANGE
CONVECTIVE SUSTENANCE LIES OUT ACRS NRN IN INTO NWRN OH WITHIN
RELATIVELY RICH THETA-E RIBBON CHARACTERIZED WITH NEAR 60F SFC
DPS. RAMPING AND WIDE BREADTH OF 925-850MB SWRLY JET FM KOMA TO
ECNTL IN ON ORDER OF 30-35 KTS WILL AID IN CONTD/INCREASING FORCED
PARCEL ASCENT THROUGH ERLY AM HOURS. LACK OF APPRECIABLE DEEP
LAYER SHEAR AND MEAGER MUCAPE ON ORDER OF 500 J/KG CURRENTLY TO
KEEP NON SEVERE TSRA COVERAGE IN ISOLD-SCT REALM. WAFFLING SFC
FNTL BOUNDARY/HIGH DEBRIS CLOUD COVER AND GRADUAL DECAY OF LLVL
JET SUPPORT LATE AM INTO MIDDAY LIKELY INSUFFICIENT FOR VIGORED
CONVECTION...BUT SHOULD FOSTER LONGEVITY OF TRAILING STRATIFORM
RAFL IN WAKE OF UPSTREAM IA/MO/IL BORDER LOCATED SHORTWAVE PASSAGE
THRU CWA INTO SRN PERIPHERY OF DOWNSTREAM WRLIES. RAIN COOLED AIR
ALONG WITH PERSISTENT BACKED FLOW NORTH OF FNTL BOUNDARY TO LIMIT
MUCAPE POTNL TO NO MORE THAN 1000 J/KG THIS AFTN AS FNTL BOUNDARY
SHIFTS NWD AMID RISING HGTS/BUCKLED MID TROP FLOW FM SERN STATES
TO SWRN GRTLKS AS DESERT SW VORTEX LIFTS MORE NWD AND ACQUIESCES
TO INTENSE PAC NW/SRN BC BEGINNING ARDENT DIG. DIFFICULT TEMP FCST
WITH SOME BREAKS PSBL SPCLY FAR SRN CWA THIS AFTN DEPENDING ON HOW
DEEP EMERGENT WARM LYR SOUTH OF FNT BECOMES...ACCENTUATED THERMAL
GRADIENT SLIGHTLY FROM NUDGE OF PRIOR FCST TOWARD CONSENSUS BLEND
OF HIR RES MODELS. MODEST FORCING AT BEST LATE AFTN INTO OVERNIGHT
WITH WANING POPS SHUNTING NWD INTO MI WITH LESSER TOKEN
PROBABILISTIC NOD FOR TSRA POTNL. AGAIN JUST A SLIGHT SHARPENING
OF GRADIENT TO TEMPS OVERNIGHT. SUSPECT BR/FG COULD ALSO BECOME AN
ISSUE WITH WIDESPREAD WETTED GROUND AS SFC TEMPS FALL BLO XOVER
TOWARD DAYBREAK.


&&

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 418 AM EDT TUE MAY 5 2015

UPPER LEVEL RIDGING WILL BE UNDERWAY AT THE START OF THE PERIOD
WITH SURFACE FRONTAL BOUNDARY LIKELY ALREADY ON ITS WAY NORTH
INTO LOWER MICHIGAN (IF NOT ALL READY THERE). SEVERAL MODELS
STILL SUGGESTING "HIT AND MISS" SHOWERS/STORMS DURING PEAK
HEATING WEDNESDAY AFTERNOON/EVE AND POSSIBLY EVEN THURSDAY. WILL
MAINTAIN DRY FORECAST BUT POPS IN THE 10 TO 14% RANGE TO HANDLE
ANYTHING THAT MIGHT POP UP. WARMER AIR WILL FINALLY MOVE IN WITH
HIGHS CLIMBING INTO THE 80S BY THURSDAY AND FRIDAY.

BEYOND EARLY FRIDAY...FORECAST BECOMES MUDDLED IN PRECIP CHANCES
ONCE AGAIN AS INFLUENCE OF SFC HIGH SHIFTS FAR ENOUGH EAST TO
ALLOW FOR INCREASING CHANCES OF SHOWERS AND STORMS IN AN
INCREASING SW FLOW. SEVERAL SUBTLE WAVES CAN BE PICKED OUT IN THE
MODELS...BUT TIMING AND TRACK OF EACH CANNOT BE RESOLVED SEVERAL
DAYS OUT WITH ANY CERTAINTY. THEREFORE...POPS WILL BE MAINTAINED
AT CHC FOR THE REMAINDER OF THE FORECAST AS THE FRONTAL BOUNDARY
DRIFTS CLOSER AND EVENTUALLY SETTLES OVERHEAD ONCE AGAIN.
TEMPERATURES WILL BE HIGHLY DEPENDENT ON CLOUD AND CONVECTIVE
SETUP EACH DAY...WARRANTING LEANING TOWARDS SUPER BLEND WHICH
ISN`T MAKING ANY MAJOR CHANGES.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 705 AM EDT TUE MAY 5 2015

OCNL IFR CONDITIONS EXPECTED TO CONT INTO EARLY AFTN AS A WK
SHRTWV LIFTS E-NE ALONG STNRY BOUNDARY LYING ACROSS CENTRAL
INDIANA RESULTING IN WIDESPREAD SHRA ACROSS NRN INDIANA. TSRA ALSO PSBL
THIS MORNING AS STRONGER FORCING MOVES THROUGH. CONDITIONS SHOULD
IMPROVE TO MVFR THIS AFTN WITH LOWERING BACK TO IFR LATE TONIGHT
AS LIGHT GRADIENT WINDS AND MOIST LOW LEVELS COMBINE FOR
RADIATIONAL COOLING BR.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SYNOPSIS...MURPHY
SHORT TERM...MURPHY
LONG TERM...FISHER
AVIATION...JT


VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.