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000
FXUS63 KILX 101152
AFDILX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
552 AM CST WED FEB 10 2010

.DISCUSSION...
ISSUED 225 AM CST WED FEB 10 2010

LATEST WATER VAPOR IMAGERY SHOWING THAT THE STRONG UPPER LOW...WHICH
CROSSED THE STATE YESTERDAY...IS NOW CENTERED IN SOUTHERN OHIO.
MAIN SURFACE LOW LOCATED OVER CENTRAL LAKE ERIE...WITH A TROUGH
EXTENDING SOUTHWEST ACROSS OUR CWA JUST NORTH OF I-70. A TIGHT
PRESSURE GRADIENT HAS RESULTED IN FREQUENT GUSTS OVER 30 MPH THE
LAST SEVERAL HOURS...BUT CALLS TO AREA LAW ENFORCEMENT NOT
YIELDING MUCH IN THE WAY OF BLOWING SNOW PROBLEMS. TEMPERATURES
HAVE BEEN RISING OVER MOST OF THE CWA SINCE LAST EVENING...BUT
SURGE OF COLDER AIR IS NOW PUSHING IN AROUND GALESBURG AND MACOMB.

THE MAIN FORECAST ISSUES FOR THIS PACKAGE INVOLVE AFFECTS OF
CLIPPER SYSTEMS FRIDAY THROUGH SUNDAY.

SHORT TERM...TODAY THROUGH FRIDAY...

HAVE CANCELLED THE WINTER WEATHER ADVISORY DUE TO THE DIMINISHING
ISSUE OF BLOWING SNOW. RUC MODEL SHOWS GUSTS OF 30-35 MPH
CONTINUING FOR A FEW MORE HOURS IN THE NORTHEAST CWA...WHICH MAY
RESULT IN SOME LIGHT BLOWING SNOW AT TIMES...BUT WINDS SHOULD
OVERALL DECREASE TODAY.

HIGH PRESSURE RIDGE TO BUILD EAST ACROSS THE MISSISSIPPI VALLEY
TONIGHT AND THURSDAY. WITH THE FRESH SNOW COVER...THE COLDEST AIR
IS EXPECTED TONIGHT. HOWEVER...SOME CLOUDINESS OFF OF LAKE
MICHIGAN MAY HELP KEEP THE EASTERN CWA A BIT WARMER. LOWS IN THE
WESTERN CWA EXPECTED TO BE IN THE ZERO TO 5 ABOVE RANGE...BUT MAY
BE BELOW ZERO IN SOME OF THE NORMALLY COLD SPOTS. MILDER WEATHER
EXPECTED FRIDAY WITH NEAR FREEZING HIGHS ACROSS THE SOUTHWEST AND
SOUTHERN CWA.

FIRST CLIPPER SYSTEM EXPECTED TO MOVE SOUTHEAST THROUGH THE MIDWEST
FRIDAY AND FRIDAY NIGHT. NAM MODEL APPEARS TO BE A SLOW OUTLIER IN
THE TIMING OF THIS SYSTEM...WITH GENERAL MODEL CONSENSUS
SUPPORTING AN AFTERNOON AND EVENING CROSSING. STILL SOME QUESTION
AS TO THE AMOUNT OF MOISTURE AVAILABLE...WITH AREAS CLOSER TO THE
MISSISSIPPI RIVER INDICATING ANYTHING SIGNIFICANT...SO WILL
RESTRICT MENTIONABLE POPS TO AREAS WEST OF I-55 DURING THE DAY
FRIDAY AND CONTINUE WITH SILENT 20S DURING THE NIGHT.

LONG TERM...SATURDAY THROUGH TUESDAY...

ECMWF AND GFS COMING INTO BETTER ALIGNMENT WITH A SECOND UPPER LOW
DROPPING SOUTHEAST OUT OF THE NORTHERN PLAINS...REACHING THE SAINT
LOUIS AREA ON SUNDAY. MAIN SURFACE LOW TO PRECEDE THE UPPER LOW BY
SEVERAL HOURS...WITH THE TRAJECTORY SUPPORTING LIGHT SNOW MAINLY
IN THE SOUTHWEST HALF OF OUR CWA. HOWEVER...WILL GO WITH 30 POPS
ACROSS THE ENTIRE CWA AS DAY 5 IS A BIT FAR OUT TO BE FINE-TUNING
THINGS THAT CLOSELY. WILL NEED TO MONITOR WHETHER POPS SHOULD BE
INCLUDED SUNDAY NIGHT AS THE LOW BEGINS TO SWING EASTWARD ACROSS
SOUTHERN ILLINOIS. BEHIND THIS...A HIGH PRESSURE RIDGE IS EXPECTED
TO BUILD EAST INTO THE MISSISSIPPI VALLEY...BRINGING QUIET WEATHER.

UPPER PATTERN CONTINUES TO SHOW RIDGING ALONG THE WEST
COAST...WITH TROUGHING OVER THE EASTERN CONUS. THIS PARTICULAR
CONFIGURATION SHOULD CONTINUE FOR SEVERAL DAYS...WITH PERSISTENTLY
BELOW NORMAL TEMPERATURES.

GEELHART
&&

.AVIATION...
ISSUED 552 AM CST WED FEB 10 2010

AN AREA OF LOW PRESSURE CONTINUES TO SPIN OVER THE EASTERN GREAT
LAKES EARLY THIS MORNING. THIS SYSTEM WILL SLOWLY TRACK EAST
THROUGH THE 12Z TAF PERIOD. GUSTY NORTHWEST WINDS EARLY TODAY WILL
DIMINISH BY LATE TODAY INTO TONIGHT AS THE PRESSURE GRADIENT
RELAXES ACROSS THE CENTRAL ILLINOIS TERMINALS. MVFR CIGS STILL
PREVAIL ACROSS THE MIDWEST IN THE WAKE OF THE SYSTEM...BUT SOME
SIGNIFICANT BREAKS HAVE OPENED UP ACROSS EASTERN IOWA AND NORTHERN
ILLINOIS. THESE BREAKS WILL IMPACT THE TERMINALS FOR A FEW HOURS
MORNING...BUT FORECAST SOUNDINGS SUGGEST THE CLOUDS SHOULD FILL
BACK IN FOR MUCH OF THE DAYLIGHT HOURS TODAY. SKIES ARE EXPECTED
TO CLEAR TONIGHT...AS HIGH PRESSURE BUILDS INTO THE REGION...IF
THEY HAVE NOT ALREADY DONE SO.

BAK
&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$