Issued by NWS Indianapolis, IN
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000 FXUS63 KIND 262317 AFDIND AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE INDIANAPOLIS IN 720 PM EDT SUN OCT 26 2008 .AVIATION... STRONG W-NW GRADIENT STILL ACROSS AREA...BUT MIXING WILL DECREASE ALLOWING SFC WINDS TO DECREASE TO 15-25 KNOT RANGE BY MIDNIGHT. GRADIENT WILL DECREASE A LITTLE MORE ON MONDAY SO WINDS SHOULD REMAIN IN SAME CATEGORY AS TONIGHT. WEATHER DEPICTION SHOWS AREA OF MVFR CIG ACROSS MUCH OF WISCONSIN AND PARTS OF MINNESOTA. SOME OF THIS WILL MOVE OUR WAY. MODELS SHOW DEEPEST LOW LEVEL MOISTURE MOVING ACROSS NORTHERN AND EAST CENTRAL INDIANA NEAR OR SHORTLY AFTER 12Z MONDAY. WILL MENTION PERIOD OF MVFR CIG AT KLAF AND KIND. KBMG AND KHUF MORE LIKELY TO STAY IN VFR CATEGORY. CLOUDS SHOULD BEGIN DIMINISHING ALL AREAS BY END OF TAF PERIOD AS HIGH PRESSURE RIDGE OVER THE PLAINS STARTS TO MOVE EASTWARD. && .PREVIOUS DISCUSSION... THE FORECAST FOCUS WILL BE ON TEMPERATURES WITH A SIGNIFICANT EARLY SEASON BLAST OF COLD AIR HEADED THIS WAY. THE SURFACE MAP SHOWS THAT THE INITIAL SURFACE COLD FRONT HAS CROSSED THROUGH CENTRAL INDIANA AS THE WINDS HAVE BECOME WESTERLY. THE MID LEVEL PATTERN REFLECTS A DEEPENING H5 TROUGH ACROSS THE UPPER MISSISSIPPI VALLEY AND LAKES REGION. STRONG RIDGING WAS PRESENT ACROSS THE SOUTHWESTERN US. MODELS ARE VERY SIMILAR FOR POPS AND TEMPS IN THE SHORT TERM. A BLEND WAS USED ON BOTH COUNTS AND UPSTREAM TEMPERATURES WERE ALSO USED. THE IMMEDIATE SHORT TERM WILL INCLUDE THE ONGOING WIND ADVISORY ACROSS THE NORTHERN COUNTIES. THIS HAS BEEN VERY SLOW TO DEVELOP AND NO GUSTS HAVE REALLY BEEN MUCH MORE THAN 30 KTS OR SO TODAY. HOWEVER...LOOKING UPSTREAM SHOWS ADVISORY CRITERIA NOW INTO CENTRAL ILLINOIS...RAPIDLY HEADING EAST. SO WILL NOT ONLY LEAVE THE ADVISORY...BUT WILL EXTEND IT TO 00Z IN THE NORTH. NEWEST BUFKIT DATA THIS AFTERNOON IS QUITE SUPPORTIVE OF GUSTS IN THE 45-50 MPH RANGE IN THE NORTH LATE THIS AFTERNOON. THE COLD AIR WILL STREAM IN OVERNIGHT WITH WINDS REMAINING RATHER STRONG. H8 TEMPS WILL FALL TO NEAR -8C BY DAYBREAK. WEAK ENERGY IN THE DEEPENING TROUGH MAY GENERATE A FEW FLURRIES TOWARDS DAYBREAK IN NORTHERN AREAS. TEMPS SHOULD FALL INTO THE MIDDLE 30S TONIGHT AS WIND AND CLOUDS WILL PREVENT ANY RADIATIONAL COOLING. ON MONDAY...IT APPEARS THAT IT WILL BE QUITE COLD FOR LATE OCTOBER. H8 TEMPS IN THE -8C RANGE ALL DAY WILL YIELD ONLY LOWER TO PERHAPS MID 40S. LOOKING UPSTREAM...TEMPS IN THIS AIRMASS OVER MINNESOTA AND EASTERN SOUTH DAKOTA HAVE BEEN IN THE LOW TO MID 30S ALL DAY. SO WILL GO IN THE LOW 40S...AND THE RECORD LOW MAX IS 40. WOULD NOT BE SURPRISED IF THIS WAS CHALLENGED WITH THE VERY COLD AIRMASS AND OVERCAST SKIES. THE FREEZE WATCH REMAINS MONDAY NIGHT AS WINDS WILL DIMINISH AND SOME PARTIAL CLEARING WILL DEVELOP. LOWS SHOULD DROP INTO THE MIDDLE AND UPPER 20S...WITH COLDEST TEMPERATURES IN THE WEST AND CENTRAL...AS IT WILL STAY CLOUDIER IN THE EAST. SINCE SOME SPOTS HAVE NOT HAD A FREEZE YET WILL CONTINUE WITH THE FREEZE WATCH ISSUED EARLIER. TUESDAY SHOULD REMAIN A VERY COLD DAY AS WELL AS THE CORE OF THE AIR WILL BE JUST TO OUR EAST. A WEAK WARMUP SHOULD TAKE PLACE IN THE WESTERN AREAS WHERE THE RETURN FLOW WILL BEGIN. HOWEVER IT WILL STILL BE WELL BELOW NORMAL AS H8 TEMPS WILL STAY WELL BELOW 0. ANOTHER COLD NIGHT IS EXPECTED TUESDAY NIGHT...AND THE AIRMASS WILL BEGIN TO WARM ALOFT AS THE H5 LOW MOVES TO THE EAST AND TAKES THE COLD POOL WITH IT. THIS MIGHT END UP BEING COLDER THAN MONDAY NIGHT AS THE RIDGE SETTLES IN. FOR THE MIDDLE AND LATTER PARTS OF THIS WEEK THERE IS EXPECTED TO BE A WARMING TREND AS THE TROUGH MOVES EAST AND THE WESTERN RIDGING PUSHES INTO THE PLAINS. MEX GUIDANCE AND HPC SHOWS TEMPS BACK TO THE 60S BY THURSDAY AND FRIDAY. && .IND WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY MORNING FOR INZ021-028>031-035>049-051>057-060>065-067>072. WIND ADVISORY UNTIL 8 PM EDT THIS AFTERNOON FOR INZ021-028>031- 035>044. && $$ AVIATION...JH PUBLIC...JOHNSON
