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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1222 AM EDT SUN AUG 31 2014

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...
ISSUED AT 327 PM EDT SAT AUG 30 2014

A SERIES OF UPPER LEVEL WAVES TRACKING THROUGH THE REGION WILL BRING 
SEVERAL CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. DRIER 
WEATHER WILL RETURN BY MIDWEEK AS HIGH PRESSURE EXPANDS INTO THE 
GREAT LAKES. CHANCES FOR STORMS WILL RETURN FOR THE END OF THE WEEK 
AND INTO THE WEEKEND AS ANOTHER FRONTAL BOUNDARY MOVES INTO THE OHIO 
VALLEY. 

&&

.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 955 PM EDT SAT AUG 30 2014

SHOWERS AND THUNDERSTORMS CONTINUE JUST NORTHWEST OF OUR FORECAST 
AREA AND ALSO NUMEROUS SHOWERS WERE OCCURRING ACROSS EXTREME 
SOUTHEAST INDIANA.  WITH THE EXCEPTION OF THOSE TWO AREAS...IT HAS 
BEEN QUIET SO FAR TONIGHT. THE SHOWERS AND THUNDERSTORMS OVER 
NORTHEAST ILLINOIS MAY BRUSH OUR FAR NORTHWEST IN THE NEXT FEW HOURS 
AND WILL ALSO KEEP HIGH POPS OVER THE FAR SOUTHEAST.

THE RAPID REFRESH MODEL SHOWS LITTLE IN THE WAY OF PRECIP FOR THE 
NEXT SEVERAL HOURS.  AS A RESULT WILL DOWNPLAY RAIN CHANCES SOME 
OVER THE REMAINDER OF OUR AREA. SHOWERS MAY INCREASE SOME AS THE 
UPPER TROUGH APPROACHES FROM THE WEST.  THUS WILL HAVE CHANCE POPS 
MOST AREAS LATE TONIGHT.

LITTLE CHANGE TO THE REST OF THE FORECAST.  TEMPERATURES SEEM TO BE 
ON TRACK WITH OVERNIGHT LOWS NEAR 70 MOST AREAS.

&&

.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 327 PM EDT SAT AUG 30 2014

FORECAST CHALLENGES FOCUS ON PRECIP CHANCES...PARTICULARLY MONDAY 
AND TUESDAY ACROSS THE FORECAST AREA.

LOW PRESSURE WILL CONTINUE TO PULL AWAY INTO QUEBEC WITH WEAK 
RIDGING ALOFT BUILDING INTO THE REGION AS THE DAY PROGRESSES. 
SHOWERS AND EMBEDDED THUNDER WILL BE ONGOING OVER FAR SOUTHERN 
FORECAST AREA IN THE MORNING GRADUALLY SHIFTING EAST OF THE REGION 
INTO THE AFTERNOON. MODEL SOUNDINGS STILL SHOW AN UNSTABLE AIRMASS 
LINGERING ACROSS THE FORECAST AREA BUT IN THE ABSENCE OF ANY 
APPRECIABLE FORCING ALOFT...EXPECT CONVECTION TO BE ISOLATED TO 
SCATTERED AT BEST AND FOCUSED ALONG AND SOUTH OF I-70 WHERE DEEPER 
MOISTURE WILL LINGER.

WEAK HIGH PRESSURE WILL OVERSPREAD THE REGION SUNDAY NIGHT AND 
OUTSIDE OF AN ISOLATED SHOWER OR STORM OVER SOUTHEAST FORECAST AREA 
WHERE SLIGHTLY BETTER MOISTURE WILL RESIDE...ANTICIPATE DRY WEATHER 
ACROSS THE REGION. MONDAY MORNING WILL START OUT DRY AS WELL BEFORE 
FOCUS SHIFTS BACK TO THE WEST IN ADVANCE OF A SHARP WAVE ALOFT 
MOVING INTO THE UPPER MISSISSIPPI VALLEY AND AN ASSOCIATED COLD 
FRONT. THE FRONT WILL MOVE INTO THE WESTERN GREAT LAKES BY MONDAY 
EVENING WITH A 30-40KT LOW LEVEL JET ADVECTING DEEPER MOISTURE BACK 
INTO THE OHIO VALLEY AHEAD OF THE FRONT. POTENTIAL FOR MORE 
ORGANIZED STORMS AND SEVERE CONVECTION MONDAY AFTERNOON AND EVENING 
AS BL SHEAR AND STORM RELATIVE HELICITIES ARE MORE PLENTIFUL WITH 
THE UPPER LEVEL FEATURE MOVING INTO THE GREAT LAKES. 

RAIN AND STORMS WILL CONTINUE MONDAY NIGHT AND TUESDAY MORNING AS 
THE FRONT SWEEPS ACROSS CENTRAL INDIANA AND THE OHIO VALLEY. WITH 
THE LOW LEVEL JET REMAINING ACROSS THE REGION...EXPECT WIDESPREAD 
STORMS WITH LOCALLY HEAVY RAIN TO IMPACT THE FORECAST AREA ALL NIGHT 
AND LIKELY POPS REMAIN WARRANTED. PRECIP WILL DIMINISH IN COVERAGE 
FROM NORTHWEST TO SOUTHEAST DURING THE COURSE OF THE DAY AS THE 
FRONT DROPS SOUTH OF THE OHIO RIVER.

TEMPS...MAVMOS GUIDANCE LOOKED REASONABLE FOR MUCH OF THE PERIOD. 
CLOUDS INITIALLY ON SUNDAY WILL LIKELY KEEP HIGHS DOWN A BIT IN THE 
UPPER 70S AND LOWER 80S. WITH CONVECTIVE IMPACTS LIKELY HOLDING OFF 
UNTIL LATER IN THE AFTERNOON MONDAY...TRENDED TOWARDS WARMER MAV FOR 
HIGHS. USED CONSMOS FOR LOWS THROUGH THE PERIOD AS ALL GUIDANCE WAS 
SIMILAR.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 327 PM EDT SAT AUG 30 2014

PRECIP CHANCES WILL GRADUALLY DECREASE AT THE BEGINNING OF THE 
EXTENDED PERIOD AS HIGH PRESSURE STRENGTHENS AT THE SURFACE AND 
FLOW BECOMES MORE ZONAL ALOFT.  NONETHELESS...KEPT MENTION OF SLIGHT 
CHANCE POPS FROM TUESDAY NIGHT THROUGH WEDNESDAY AS A FRONTAL 
BOUNDARY STALLS OVER THE TENNESSEE VALLEY.  BY THURSDAY...A WEAK 
SHORT WAVE IN THE UPPER FLOW WILL INCREASE PRECIP CHANCES 
AGAIN...AND A WARM FRONT AT THE END OF THE EXTENDED PERIOD WILL 
INCREASE SHOWER/THUNDERSTORM CHANCES EVEN FURTHER BY THURSDAY 
NIGHT.  THIS WARM FRONT WILL ALSO RESULT IN A WARM UP AFTER THE COLD 
FRONT EARLIER IN THE LONG TERM PERIOD.  HIGH TEMPERATURES WILL CLIMB 
BACK INTO THE UPPER 80S/LOW 90S ON THURSDAY AND FRIDAY.  TUESDAY AND 
WEDNESDAY...HIGHS WILL BE CLOSER TO NORMAL WITH READINGS IN THE LOW 
TO MID 80S.  OVERNIGHT LOWS WILL TREND FROM THE LOW TO MID 60S AT 
THE BEGINNING OF THE EXTENDED PERIOD....TO MID TO UPPER 60S BY THE 
END OF THE PERIOD.

&&

.AVIATION /DISCUSSION FOR 310600Z TAF ISSUANCE/...

ISSUED AT 1222 AM EDT SUN AUG 31 2014

KLAF COULD GET EAST ENOUGH TO IMPACT KLAF WITHIN THE NEXT COUPLE OF 
HOURS AND WILL CONTINUE TO CARRY VCTS THERE WITH TEMPO THUNDER FOR A 
COUPLE OF HOURS. AT KHUF AND KIND THINK DRY WEATHER WILL PREVAIL 
THROUGH THE NIGHT. EXPECT MORE WIDESPREAD LOWER CEILINGS /AROUND 
1500 FT/ LATER DURING THE OVERNIGHT AND WITH THE HUMID AIR MASS 
COULD SEE SOME VISIBILITY REDUCTIONS AS WELL BUT STILL MVFR. LOWER 
CEILINGS COULD HANG AROUND UNTIL AFTERNOON BEFORE SCATTERING UP. 

WINDS SHOULD REMAIN OUT OF THE SSW THROUGH THE OVERNIGHT AROUND 5-10 
KTS.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...RYAN
NEAR TERM...JH
SHORT TERM...RYAN
LONG TERM....TDUD
AVIATION...CP

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