New winter product keeps LES advisory going
new LOT Aviation update
OR THE 18Z TAFS...
THE PRIMARY FORECAST CONCERN THROUGH THE NEXT 24-30 HOURS REVOLVES
AROUND A PENCIL-THIN BAND OF LAKE EFFECT SNOW TAKING AIM AT MDW
AND EVENTUALLY GYY. OTHERWISE, GENERALLY QUIET CONDITIONS ARE
EXPECTED.
THE AFOREMENTIONED PENCIL-THIN BAND OF LAKE EFFECT SNOW IS
CURRENTLY ENTERING NORTHEASTERN ILLINOIS JUST NORTH OF DOWNTOWN
CHICAGO, AND HAS SHOWN RECENT SIGNS OF INTENSIFICATION WITH
POCKETS OF RADAR REFLECTIVITY VALUES NOW APPROACHING 25-30 DBZ.
SUCH VALUES WOULD CORRESPOND TO VISIBILITY DROPS AS LOW AS 1 MILE
(IF NOT A SMIDGE LOWER). THE EYE TEST SUGGESTS THE BAND WILL
LIKELY GET WITHIN A 5 MILE RADIUS OF MDW, BUT PERHAPS STAY A
SLIVER EAST OF THE ACTUAL AIRFIELD. HOWEVER, LITTLE WIGGLES
WESTWARD MAY AFFORD BRIEF DROPS IN VISIBILITY TO A MILE. THE BAND
IS EXPECTED TO DRIFT EASTWARD LATER THIS AFTERNOON TOWARD GYY, AND
EVENTUALLY FURTHER EAST INTO NORTHWESTERN INDIANA. ALL IN ALL,
THE INHERITED TEMPO GROUP REMAINS APPROPRIATE WITH ONLY MINOR
ADJUSTMENTS TO TIMING REQUIRED. AT ORD, THE POTENTIAL FOR THE BAND
TO SWING WEST IS VERY LOW. EVEN SO, OCCASIONAL SPITS OF FLURRIES
CAN'T BE RULED OUT THROUGH EARLY AFTERNOON.