000
FXUS63 KIWX 041133
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
633 AM EST TUE MAR 4 2014

.SYNOPSIS...
ISSUED AT 430 AM EST TUE MAR 4 2014

A WEAK UPPER LEVEL TROUGH WILL MOVE EAST ACROSS THE GREAT LAKES
TODAY LIKELY CAUSING A PERIOD OF LIGHT SNOW OVER LOWER MICHIGAN...
OTHERWISE... HIGH PRESSURE CENTERED OVER PENNSYLVANIA WILL
CONTINUE TO CAUSE DRY AND COLD WEATHER ACROSS THE REGION.

A COLD FRONT WILL DROP SOUTH ACROSS THE GREAT LAKES TONIGHT... AND
COMBINE WITH ANOTHER UPPER LEVEL TROUGH MOVING EAST FROM THE
PLAINS... TO CAUSE LIGHT SNOW TO SPREAD INTO NORTHEAST ILLINOIS...
SOUTHERN LOWER MICHIGAN... AND NORTHERN INDIANA LATE.

TEMPERATURES WILL CONTINUE WELL BELOW NORMAL... WITH HIGHS GENERALLY
IN THE 20S TODAY... AND LOWS 10 TO 15 TONIGHT.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 430 AM EST TUE MAR 4 2014

SHRTWV MOVG ESE ACROSS NRN IL/SRN WI WILL MOVE THROUGH OUR CWA
THIS MORNING. MAIN IMPACT OF THIS SYSTEM WILL BE CONSIDERABLE
CLOUDINESS AS BULK OF PRECIP EVAPORATING BEFORE REACHING THE
GROUND THIS FAR SOUTH... THOUGH A PERIOD OF LIGHT SNOW WILL LIKELY
AT LEAST CLIP NRN PORTION OF BERRIEN COUNTY THIS MORNING. WK
GRADIENT... SNOW COVER... CONSIDERABLE CLOUDINESS... AND LINGERING
SHALLOW ARCTIC AIRMASS SUGGEST TEMPS WILL REMAIN WELL BLO NORMAL
TODAY WITH HIGHS IN THE L-M20S.

UPR LEVEL TROF WILL ROTATE AROUND QUEBEC LOW ACROSS THE UPR GRTLKS
TONIGHT WITH AN ACCOMPANYING SFC BACKDOOR TYPE CDFNT MOVG THROUGH
OUR AREA LATE. ANOTHER SHRTWV WILL MOVE ESE FROM THE PAC NW INTO
THE MID/UPR MS VALLEY OVERNIGHT. COMBINATION OF THESE TWO SYSTEMS SHOULD
PROVIDE DECENT FORCING IN THE FORM OF MID LEVEL CONFLUENCE AND LOW
LEVEL CONVERGENCE/FRONTOGENESIS... LIKELY RESULTING IN LIGHT SNOW
SPREADING INTO NWRN PORTION OF THE CWA LATE. CONSIDERABLE CLOUDINESS
SHOULD LIMIT TEMP DROP OVERNIGHT DESPITE WK GRADIENT MIXING AND SNOW
COVER WITH LOWS EXPECTED MAINLY IN THE 10-15 RANGE.

&&

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 430 AM EST TUE MAR 4 2014

A SERIES OF UPPER LEVEL TROFS IN RATHER CHAOTIC FLOW WILL BRING
CHANCES FOR MAINLY SNOW THROUGHOUT THIS PERIOD. SOME FLATTENING OF
THE UPPER AIR PATTERN THIS PERIOD WILL ALLOW FOR A HIGHER ZONAL
FLOW... ACCOMPANIED BY MODERATING TEMPERATURES. NORMAL HIGHS BY
SATURDAY ARE 43F AND 46F RESPECTIVELY AT SOUTH BEND AND FORT WAYNE.
TEMPERATURES SHOULD START MUCH BELOW NORMAL WEDNESDAY...BUT FINALLY
RISE TO NEAR NORMAL MONDAY. FOR THE ARRIVAL OF THE FIRST UPPER
TROF...KEPT A CHANCE FOR SNOW WEDNESDAY THROUGH WEDNESDAY NIGHT.
LIMITED MOISTURE AND LIFT SHOULD KEEP SNOW AMOUNTS UNDER 2
INCHES...WITH THE HIGHEST AMOUNTS IN THE WEST. THE ECMWF APPEARS TO
HAVE THE BEST HANDLE ON THIS SYSTEM WITH 2-3 G/KG MOISTURE ON THE
290K SFC. HOWEVER...SATURATION AND LIFT BECOME LIMITED...SO SNOW
AMOUNTS OVER EASTERN AREAS SHOULD BE AROUND AN INCH OR LESS. A
SIMILAR SCENARIO WILL SET UP FRIDAY THROUGH SATURDAY NIGHT WITH
LIGHT MAINLY SNOW AMOUNTS. TEMPERATURES SHOULD BE A LITTLE
WARMER...BUT GIVEN WET BULB TEMPERATURES REMAINING MOSTLY BELOW
ZERO...THE PRECIPITATION SHOULD BE MAINLY SNOW. ONE LAST SYSTEM WAS
ON THE HORIZON PER ECMWF SOLUTION. KEPT MONDAY DRY...BUT THE ECMWF
HAS BEEN CONSISTENT FOR 3 RUNS WITH A STRONG SYSTEM MOVING INTO THE
OHIO VALLEY REGION TUESDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 627 AM EST TUE MAR 4 2014

SHRTWV MOVG THROUGH THE GRTLKS THIS MORNING WILL RESULT IN MAINLY
MID CLOUDS ACROSS THE AREA WITH SOME VFR FLURRIES PSBL AT SBN. A
BACKDOOR CDFNT WILL DROP SOUTH ACROSS THE AREA TONIGHT CAUSING
LIGHT SW WINDS TO VEER TO NE. A WK SHRTWV WILL MOVE ESE FROM THE
PLAINS ALONG THE LOW LEVEL BAROCLINIC ZONE LIKELY CAUSING SOME -SN
WITH MVFR CONDITIONS TO SPREAD INTO THE AREA TOWARD THE END OF THE
TAF PERIOD.

&&

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

$$

SYNOPSIS...JT
SHORT TERM...SKIPPER
LONG TERM...JT
AVIATION...JT


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

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