000
FXUS63 KIWX 060542
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
1242 AM EST FRI MAR 6 2015

.SYNOPSIS...
ISSUED AT 851 PM EST THU MAR 5 2015

MOSTLY CLEAR SKIES WILL CONTINUE INTO THE OVERNIGHT HOURS. EXTREMELY
COLD OVERNIGHT LOWS WILL DROP TO ZERO TO 5 BELOW ZERO. WIND CHILL
VALUES ARE EXPECTED TO DROP TO AS LOW AS -10 DEGREES OVERNIGHT. HIGH
TEMPERATURES ON FRIDAY WILL BE IN THE MIDDLE TO UPPER 20S.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 414 PM EST THU MAR 5 2015

RAPID EWD EXODUS OF POS TILTED MID TROPOSPHERIC TROF THROUGH LWR
GRTLKS INTO ERN STATES FOLLOWED BY LESSER AMPLITUDE TROFFING INTO
WRN GRTLKS FRI TO SOLIDIFY DRY CP ARCTIC AIRMASS ACRS REGION
OVERNIGHT INTO EARLY FRI. INCRS WRLY FLOW UPWIND OF LK MI TO
AFFORD DRY AIR ENTRAINMENT WITH ANY LINGERING FLURRIES SUCCUMBING
TO DEMISE NEAR SUNSET FOLLOWED BY RAPID LONGWAVE RADIATIONAL
LOSSES. AS SFC RIDGELINE SETTLES INTO OH VLY ON FRI AND TWO HIGH
BELTED CLIPPER SYSTEMS TRACK WELL N-NW...ONE INTO FAR SRN HUDSON
BAY/NRN JAMES BAY THE OTHER TO LAKE WINNIPEG BY 00 UTC SAT.
EXTREME DRY UPSTREAM AIR MASS CHARACTERIZED BY 20 PERCENT OF
NORMAL PWAT...LTE 0.10 INCHES THROUGHOUT UPR/MID MS VLY. STRONG
WAA SFC-925MB ALONG WITH HIGH EARLY MARCH SUN ANGLE/INSOLATION
WITH NEAR 10C/12 HR RISES AT 925MB BY 21C IN SWRN CWA. AS SUCH
HAVE GONE A BIT HIR WITH TEMPS TMRW...STRONG DIURNAL PLUS...MUTED
ON ERN CWA ALONG TRAILING PERIPHERY OF EXITING COLD POOL.

&&

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 414 PM EST THU MAR 5 2015

THE START OF THE WARMUP BEGINS DURING THE DAY SATURDAY. DO NOT
EXPECT MUCH OF A MAX TEMP DIFFERENCE BETWEEN SATURDAY AND SUNDAY
AS MOST OF THE ENERGY WILL BE USED TO MELT SNOW.
ADDITIONALLY...ANOTHER WEAK SHORTWAVE SLIPS ACROSS THE GREAT
LAKES DURING THE DAY SUNDAY AND THIS WILL ACT TO TEMPER THE WARM
UP.

THE BIGGEST CHANGE IN TEMPERATURES WILL OCCUR MIDWEEK INTO THE
LATTER PART OF THE EXTENDED FORECAST. GIVEN THE FROST DEPTH SNOW
MELT WILL CREATE ISOLATED FLOODING IN LOW LYING AREA AND POOR
DRAINAGE LOCATIONS. WILL NEED TO CLOSELY MONITOR WATERWAYS FOR
ICE JAMS AS THE RIVERS BEGIN TO SHED ICE AND FLOWS INCREASE.

NO PRECIPITATION DURING THE WARM-UP AND THUS LITTLE CONTRIBUTION
TO THE WATER/FLOW.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1228 AM EST FRI MAR 6 2015

VFR CONDITIONS ARE EXPECTED THROUGH THIS FORECAST VALID PERIOD AS
A RIDGE OF HIGH PRESSURE SETTLES ACROSS THE OHIO RIVER VALLEY. AS
THIS OCCURS INTO EARLY FRIDAY MORNING...LIGHT AND VARIABLE WINDS
WILL BECOME SOUTHERLY...WITH STEADILY INCREASING GRADIENT
SUPPORTING GUSTS AROUND 20 KNOTS BY LATE FRIDAY MORNING INTO FRIDAY
AFTERNOON. AN UPPER LEVEL SHORT WAVE ACROSS THE CENTRAL PLAINS
WILL BE MOISTURE STARVED AS IT REACHES THE SOUTHERN GREAT
LAKES...WITH NOTHING MORE THAN SCT-BKN MID LEVEL CLOUD FRIDAY.
ANOTHER FAST MOVING WAVE WILL DIVE SOUTHEAST INTO THE WESTERN
GREAT LAKES TOWARD SATURDAY MORNING WITH SOME LOW CLOUD
DEVELOPMENT POSSIBLE IN ADVANCE OF THIS WAVE...BUT MORE LIKELY
OUTSIDE OF THIS FORECAST VALID PERIOD.

&&

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

$$

SYNOPSIS...MURPHY/BENTLEY/REHBEIN
SHORT TERM...MURPHY
LONG TERM...LEWIS
AVIATION...MARSILI


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