000
FXUS63 KLOT 301145
AFDLOT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
645 AM CDT SAT AUG 30 2008

.DISCUSSION...
240 AM CDT

WITH CLEAR SKIES IN ALL DIRECTIONS AND HIGH PRESSURE BUILDING IN
FROM THE WEST TO SECURE SAME...THERE ISNT MUCH ISSUE FOR DISCUSSION
FOR TODAYS SCENARIO. CU SHUD BE AT A MINIMUM IF NOT EXISTENT UNDER
SUCH STRONG SUBSIDENCE. THE HIGH CENTER IS HOWEVER SHIFTING EAST
OF THE AREA BY SUNSET WITH WINDS VEERING TO THE SOUTHEAST BY
SUNDAY MORNING.

GULF MSTR BEGINS WORKING UP INTO THE PLAINS FROM THE TX COAST OVER
THE WEEKEND WITH A DECENT 30 TO 40 KT SOUTHERLY LLJ PUMPING THIS
MSTR NWD INTO THE UPR MS VLY BY MONDAY. THIS TREND CONTINUES THRU
TUESDAY AS A WAVE COMES BEARING ACROSS THE UPR MS VLY FROM THE
DAKOTAS. MEANWHILE GUSTAV MAKES LANDFALL IN LOUISIANA LATE IN THE
DAY MONDAY AND BEGINS TO HARBOR MOST OF THAT MSTR OVER THE LOWER MS
VLY...LEAVING LTL TO PASS NWD THRU THE PLAINS BY THE END OF THE DAY
ON TUESDAY. VIEWING MODELS WITH SUSPICION ON THE OUTCOME OF THESE
TWO FEATURES...I WUD SAY THAT BEST LIFT FROM THE NRN SHORT WAVE WUD
BE ACROSS THE GREAT LAKES WHILE MOST OF THE MAJOR STORM ACTIVITY
WUD CONFINE ITSELF TO GUSTAVS INFLUENCE OVER THE LOWER MS VLY THRU
THURSDAY. FROPA FROM THE NRN SYSTEM WUD CROSS THRU NRN IL AND
INDIANA THURS NGT AND FRIDAY...WHILE STORMS STILL RAGE OVER TX
AND THE LOWER MS VLY.

AM LEAVING EXTENDED FORECAST AS IS FOR NOW...PENDING MORE SOLID
RESOLUTION ON GUSTAVS OUTCOME.

TEMPERATURE-WISE...THE EXTENSIVE PERIOD OF SOUTH FLOW THRU THURSDAY
WUD PERMIT SUMMER TEMPS TO WORK THRU THE 80S DURING THE DAY. THESE
WUD BE DAMPENED ONLY BY CLOUD COVER AND INCREASING RH VALUES. WILL
START SEEING SOME 90S SOUTH ON MONDAY...THREATENING THE NORTH BY
TUESDAY AND WEDNESDAY BUT NOT MAKING IT. INCREASING CLOUDS AND
PSBL RAIN BY THURSDAY WILL LIMIT TEMP RISES ONLY INTO THE 80S.

RLB

&&

.AVIATION...
630 PM CDT

12Z TAFS...NO CHANGES NECESSARY TO GOING TAFS. THE LARGE RIDGE OF
HIGH PRESSURE CONTINUES TO SLWLY SAG SOUTH...WITH THE AXIS NOW
ALONG THE KANKAKEE RIVER. THE HIGH PRESSURE WILL REMAIN OVER THE
AREA THROUGH THE PERIOD. SKIES WILL REMAIN GENERALLY SKC THROUGH
THE PERIOD WITH PERHAPS JUST A VERY FEW CU DURG THE AFTERNOON.
THE MAIN CONCERN WILL BE WIND DIRECTION THIS AFTERNOON. FOR THE
EARLY MORNING HOURS...EXPECT CALM WINDS TO CONTINUE WITH THE RIDGE
AXIS JUST SOUTH OF THE TERMINALS...BUT WITH A VERY WEAK PRESSURE GRADIENT
IN PLACE...LAKE BREEZE DEVELOPMENT IS LIKELY AGAIN THIS AFTERNOON...WHICH
SHOULD TURN WINDS TO MORE ESELY OR ELY AT ORD/MDW/GYY. RFD/DPA
SHOULD REMAIN MORE SYNOPTICALLY INFLUENCED AND MORE SLY. WINDS
SHOULD GO LGT/VRBL AGAIN AT SUNSET. WITH THE DRY AIRMASS IN
PLACE...DO NOT EXPECT ANY VSBY RESTRICTIONS TONIGHT.

KREIN

&&

.MARINE...

1230 PM CDT

HIGH PRESSURE CENTERED OVER NORTHERN ILLINOIS WILL MOVE EAST
ACROSS THE SOUTHERN GREAT LAKES SATURDAY. THE HIGH WILL CONTINUE
EAST ACROSS THE EASTERN GREAT LAKES SUNDAY AND THEN REMAIN THERE
THROUGH WEDNESDAY. LOW PRESSURE IS EXPECTED TO DEVELOP OVER THE
NORTHERN ROCKIES TONIGHT AND MOVE OUT OVER THE NORTHERN PLAINS ON
SUNDAY. THE LOW WILL BE FORCED TO TRACK NORTHEAST INTO SOUTHERN
ONTARIO MONDAY NIGHT...AROUND THE WESTERN PERIPHERY OF THE
STATIONARY HIGH. ANOTHER LOW IS FORECAST TO DEVELOP OVER THE
CENTRAL ROCKIES MONDAY NIGHT AND QUICKLY TRACK INTO THE UPPER
MISSISSIPPI VALLEY TUESDAY. THIS WILL ALLOW FOR GENERALLY
SOUTHERLY WINDS ACROSS LAKE MICHIGAN BEGINNING TONIGHT AND
CONTINUING THROUGH MIDWEEK.

KREIN

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$