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000 FXUS63 KIND 271919 AFDIND AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE INDIANAPOLIS IN 319 PM EDT MON OCT 27 2008 .DISCUSSION... THE FOCUS WILL BE ON TEMPERATURES IN THE NEXT FEW DAYS AS A COLD AIRMASS WILL BE DISLODGED FROM INDIANA AND SHOVED EAST. THE SURFACE MAP THIS AFTERNOON SHOWS HIGH PRESSURE CENTERED OVER THE LOWER MISSISSIPPI VALLEY WITH A STRONG LOW OFF THE EAST COAST. THE FLOW ALOFT HAD A CUTOFF OVER THE EAST COAST AND RIDGING OVER THE FOUR CORNERS. THE COMBINATION OF THESE FACTORS WAS PRODUCING A STRONG AND DEEP CYCLONIC FLOW OVER THE MIDWEST. THE GUIDANCE VALUES CONTINUE TO BE PRETTY SIMILAR IN THEIR HANDLING OF POPS AND TEMPS OVER THE NEXT FEW PERIODS. WILL CONTINUE TO USE A BLEND. FOR THE REMAINDER OF THE EVENING THERE WILL BE SOME SCATTERED FLURRIES OR SPRINKLES. TEMPERATURES REMAIN IN THE MID 40S SO DURING THE DAYLIGHT HOURS IT WILL PROBABLY BE IN A LIQUID FORM. THERE IS A VORT MAX OVER SOUTHERN WISCONSIN THAT SHOULD CROSS THE AREA TONIGHT AND SO WILL INCLUDE SLIGHT CHANCE AND CHANCE POPS IN OUR NORTHEAST ZONES WHERE THERE IS A BETTER SHOT AT MEASURABLE PRECIP TONIGHT. THIS WILL LIKELY BE IN THE FORM OF SNOW SHOWERS OVERNIGHT AS THE SOUNDING SHOWS A BELOW FREEZING COLUMN FROM THE SURFACE ON UPWARDS. TEMPS TONIGHT ARE EXPECTED IN THE 29-32 DEGREE RANGE...WARMEST IN OUR EAST WHERE CLOUDS ARE GOING TO BE THICKER. SO WILL KEEP THE FREEZE WARNING GOING TONIGHT SINCE SUB-FREEZING TEMPERATURES ARE EXPECTED TO OCCUR. ON TUESDAY THE UPPER LOW WILL KICK NORTH INTO SOUTHEAST CANADA. WE WILL REMAIN IN THE CYCLONIC INFLUENCE IN INDIANA. HIGH PRESSURE AT THE SURFACE WILL SLOWLY BUILD IN AND ALLOW THE WINDS TO RELAX A BIT. TEMPS TOMORROW WILL REMAIN IN THE MIDDLE 40S AGAIN WITH H8 TEMPS AROUND -6C. OVERNIGHT TUESDAY IT WILL PROBABLY BE THE COLDEST NIGHT OF THE SEASON SO FAR. THERE WILL BE A RELAXING OF THE GRADIENT AND A REDUCTION OF CLOUDINESS AS THE UPPER LOW MOVES FARTHER AWAY. MOS GUIDANCE IS SHOWING TEMPS ABOUT 2 TO 3 DEGREES COLDER THAN TONIGHT. WILL HAVE A FREEZE WATCH FOR TUESDAY NIGHT SINCE SUB- FREEZING CONDITIONS ARE EXPECTED. ON WEDNESDAY IT SHOULD BE A MUCH WARMER DAY AS THE SURFACE HIGH PULLS EAST INTO THE SOUTHERN US. H8 TEMPS WILL WARM SHARPLY FROM THE WEST TO NEAR +4C BY EVENING. MOST OF THIS WARMING WILL BE ALOFT WITH AN INVERTED SOUNDING EXPECTED. BUT IT SHOULD BE SIGNIFICANTLY WARMER THAN MONDAY AND TUESDAY...AS HIGHS IN THE MID 50S CENTRAL AND NEAR 60 IN THE FAR SOUTHWEST. TEMPS WILL STAY JUST ABOVE FREEZING WEDNESDAY NIGHT AS A BIG MODERATION IN THE OVERALL AIRMASS OCCURS. WINDS WILL SHIFT MORE SOUTHERLY OVERNIGHT AS WELL. BY THE LATE WEEK THERE WILL BE A BIG WARMING TREND AS THE HIGH PRESSURE DRIFTS SLOWLY OFF THE EAST COAST AND ACTS ALMOST LIKE A BERMUDA HIGH IN PUMPING H8 TEMPS OVER +10C BY THURSDAY AND FRIDAY. HIGHS WELL INTO THE 60S ARE EXPECTED ON THESE DAYS. OVERNIGHT LOWS WILL REMAIN ONLY IN THE 40S. HALLOWEEN LOOKS MILD AND DRY AT THIS POINT. && .AVIATION... DISCUSSION FOR 18Z TAFS. LOOK FOR VFR CONDS TO PERSIST THROUGH THE PERIOD. WIND GUSTS WILL LIKELY PERSIST THROUGH THE NIGHT AS WELL ALTHOUGH SOME DECREASE IN SPEEDS WILL OCCUR. ANY LAKE EFFECT PLUME OF RAIN OR SNOW SHOWERS SHOULD STAY NE OF THE IND/LAF SITES SO WE WILL KEEP THE FCST DRY. && .IND WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR INZ021-028>031-035>049-051>057-060>065-067>072. FREEZE WARNING FROM MIDNIGHT TONIGHT TO 10 AM EDT TUESDAY FOR INZ021-028>031-035>049-051>057-060>065-067>072. && $$ AVIATION...CO PUBLIC...JOHNSON
