1/26/09 Early Morning

I will highlight key wording from NWS in their MFD ( Morning Forecast Discussion )

I will post this in two blogs for easier reading.

MAIN FORECAST CHALLENGE FOR THE SHORT TERM PERIOD WILL BE SIGNIFICANT WEATHER BEGINNING TO IMPACT THE AREA TONIGHT.

DURING THE DAYTIME HOURS...HIGH PRESSURE BEGINS TO BREAK DOWN OFFTHE COAST OF FLORIDA AS A SURFACE LOW BEGINS TO NOSE INTO THE REGIONFROM THE SOUTHERN PLAINS. AS MOISTURE INCREASES SO WILL LOW LEVELCLOUDS DURING THE DAY AND CONDITIONS WILL REMAIN MOSTLY CLOUDY.EXPECT HIGHS AROUND 30 NORTH TO NEAR 40 ALONG THE KY/TN BORDER.

BY MONDAY EVENING...AN INVERTED SURFACE TROUGH BEGINS TO SET UP OVERTHE REGION AND STRENGTHEN DURING THE OVERNIGHT HOURS. PLENTY OF GULFMOISTURE WILL BE TAPPED AND MODELS ARE FAIRLY CONSISTENT IN BRINGINGIN AREA OF HIGH QPF BY 03Z IN THE FAR WEST AND SPREADING EASTWARDTHROUGH THE NIGHT. SATURATED THERMODYNAMIC PROFILES...MID AND UPPERLEVEL JET SUPPORT ALONG WITH SOME FRONTOGENETICAL FORCING WILL HELPCREATE HIGH PRECIPITATION RATES AFTER 06Z TUESDAY. CURRENT FORECASTSOUNDINGS INDICATE THAT PRECIPITATION WILL BE ALL SNOW ACROSSSOUTHERN INDIANA AND NORTH CENTRAL KENTUCKY THROUGH MONDAY NIGHT.FURTHER SOUTH ACROSS CENTRAL KENTUCKY...A MIX OF SNOW AND SLEET ISEXPECTED AND SOUTH CENTRAL KENTUCKY CAN EXPECT MAINLY FREEZING RAINAND SLEET THROUGH MONDAY NIGHT AS WARMER AIR NOSES IN AT MID LEVELS.

AT THIS TIME...QPF AMOUNTS AND THERMODYNAMIC PROFILES SUGGEST THATMODERATE TO HEAVY SNOWFALL WILL RESULT IN AROUND 4 INCHES OF SNOW ACCUMULATION ACROSS SOUTHERN INDIANA AND FAR NORTH CENTRALKENTUCKY...INCLUDING THE LOUISVILLE AND LEXINGTON METRO AREAS.FURTHER SOUTH WERE SOME SLEET IS EXPECTED...SNOW ACCUMULATIONAMOUNTS WILL BE AROUND 1 TO 3 INCHES DEPENDING ON THE AMOUNT OFSLEET THAT FALLS. ACROSS SOUTH CENTRAL KENTUCKY...AROUND ONE TO TWOTENTHS OF AN INCH OF ICE ACCUMULATION CAN BE EXPECTED.

PRECIPITATION WILL MOVE INTO WEST CENTRAL KENTUCKY AROUND 03ZTUESDAY AND ARRIVE IN LEX AROUND 06Z AND QUICKLY MOVE ACROSS THEREST OF THE FORECAST AREA. THEREFORE...EXPECT SLIGHTLY HIGHERPRECIPITATION AMOUNTS IN THE WEST THAN IN THE EAST...HOWEVER WITHPRECIP RATES NOT INCREASING UNTIL AFTER 06Z DO NOT EXPECT THISDIFFERENCE TO BE OF MUCH SIGNIFICANCE.

The most important part of this discussion:

A WINTER STORM WARNING IS PLANNED FOR THE NORTHERN TWO THIRDS OF THEFORECAST AREA FROM MONDAY EVENING THROUGH TUESDAY NIGHT.

AN ICE STORM WARNING WILL BE ISSUED FOR THE SOUTHERN THIRD OF THE FORECASTAREA FROM MONDAY EVENING THROUGH TUESDAY AFTERNOON.

I would predict to say the line will be from Elizabethtown northward will be issued under Winter Storm Warning and from Elizabethtown south to be issued as ICE STORM WARNING.

Areas that receive significant icing should expect prolong power outages and extended school closings.

This is only for MONDAY Discussion!