Area Forecast Discussion
Issued by NWS Indianapolis, IN

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000
FXUS63 KIND 291829
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
229 PM EDT TUE JUL 29 2014

.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...
ISSUED AT 158 PM EDT TUE JUL 29 2014

INDIANA WEATHER WILL REMAIN IN ALMOST THE SAME PATTERN THROUGH EARLY
NEXT WEEK. LOW PRESSURE IS EXPECTED TO REMAIN TO OUR NORTH AND EAST.
HIGH PRESSURE IS FORECAST TO STAY TO THE SOUTH AND WEST. THIS
COMBINATION WILL KEEP AIR FROM CANADA FLOWING INTO STATE...WHICH IN
TURN WILL KEEP TEMPERATURES BELOW NORMAL.

BESIDE KEEPING US COOL...THE WEATHER PATTERNS IN THE FORECAST
SHOULD GIVE US A CHANCE OF SHOWERS OR THUNDERSTORMS ALMOST EVERY
DAY.

&&

.NEAR TERM /TONIGHT/...

ISSUED AT 158 PM EDT TUE JUL 29 2014

THE MAJOR QUESTION IS THE CHANCE OF RAIN.

THE LATEST SATELLITE WATER VAPOR IMAGES SHOW A SHORT WAVE
APPROACHING FROM MICHIGAN. THIS WAVE IS DECEPTIVE IN THE SENSE IT
LAGS THE CLOUD BAND OVER INDIANA IN THE VISIBLE PICTURES.

WITH THE SHORT WAVE INBOUND AND THE ENTIRE AREA IN A COOL CYCLONIC
FLOW...THERE IS A CHANCE OF SHOWERS TONIGHT EXCEPT IN THE SOUTH
WHERE THE EFFECTS OF THE WAVE WILL BE WEAKEST. THE QPF FIELDS FROM
THE LATEST RUC ALSO SUPPORT THE IDEA OF SOME RAIN IN THE NORTHERN
CWA.

THE NAM POPS SEEM CORRUPTED UNLESS ONE IS WILLING TO BELIEVE 66
PERCENT AT MUNCIE WITH 30 PERCENT AT FORT WAYNE MAKES SENSE IN THIS
PATTERN. THE MAV POPS SEEM TOO LOW BASED ON THE ABOVE REASONING
ABOUT THE SHORT WAVE AND RUC QPF.

ADDING 10 PERCENT TO THE MAV POPS DOES PRODUCE A SOLUTION THAT FITS
WELL WITH HOW THE SITUATION IS EVOLVING. THAT IS...A SLIGHT CHANCE
OR A CHANCE IN THE NORTH...WITH THE SOUTH REMAINING DRY.

SKIES SHOULD BE PARTLY CLOUDY OVERNIGHT AS CLOUD PATCHES CONTINUE TO
MOVE BY IN THE CYCLONIC FLOW.

GUIDANCE TEMPERATES ARE CLOSE. THEY LOOK REASONABLE CONSIDERING
WHAT HAS OCCURRED RECENTLY AND THAT THE SITUATION IS NOT CHANGING
MUCH.  WHERE THEY DIFFER A CONSENSUS WILL BE USED.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...

ISSUED AT 158 PM EDT TUE JUL 29 2014

THE CHANCE OF PRECIPITATION IS THE MAIN ISSUE.

THE DETERMINISTIC FIELDS OF THE MODELS ARE CLOSE THROUGH THE PERIOD.
THERE WONT BE MUCH CHANGE IN THE COOL CYCLONIC FLOW OVER THE AREA.

THE ISSUE COMES DOWN TO WHICH STATISTICAL GUIDANCE IS HANDLING THE
SITUATION BEST...IF ANY IS.

THE MET POPS SEEM TOO WET...SOMETIMES MUCH TOO WET...IN THE ABSENCE
OF ANY SYSTEM THAT WILL PRODUCE A LOT OF FORCING.

MEANWHILE...THE MAV POPS LOOK TOO LOW.  THE GFS AND NAM BOTH HAVE
MODERATELY UNSTABLE AFTERNOON LIFTED INDICES. GIVEN SMALL TROUGHS
ARE GOING TO CONTINUE PASSING IN THE CYCLONIC FLOW...THIS
FORECAST PACKAGE WILL HAVE A CHANCE OF DAYTIME CONVECTION IN THE
NORTH. THE SOUTH WILL PROBABLY STAY DRY IN A DRIER FLOW NOT
AFFECTED BY THE LAKES.

IN AND OUT CLOUDS WILL CONTINUE FROM THE EFFECTS OF WEAK TROUGHS
PASSING AND DAYTIME HEATING.

THE MODEL THERMAL FIELDS ARE VERY CLOSE. ALL SUPPORT SLOW WARMING AS
THE CYCLONIC FLOW OVER THE AREA SLOWLY MOVES EAST. THE STATISTICAL
GUIDANCE SEEMS TO REFLECT THIS WELL. TO THE EXTENT THERE ARE
DIFFERENCES...A CONSENSUS OF THAT WILL BE USED.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 229 PM EDT TUE JUL 29 2014

GRADUALLY WARMER AND DRIER CONDITIONS ARE ANTICIPATED THROUGH THE
EXTENDED PERIOD AS THE STAGNANT UPPER TROUGH CENTERED OVER THE
REGION FINALLY LIFTS OUT LATE IN THE WEEKEND.

WITH THE UPPER TROUGH STILL IN THE AREA SATURDAY...WILL CARRY LOW
CHANCE POPS FOR SCATTERED AFTERNOON CONVECTION. THE SYSTEM BEGINS
TO PULL AWAY TO THE EAST SUNDAY WITH DRIER AIR FILTERING IN AS
HIGH PRESSURE BUILDS IN FROM THE WEST. UPPER PATTERN TRANSITIONS
INTO NORTHWEST FLOW BETWEEN A RIDGE OVER THE CENTRAL PLAINS AND
THE DEPARTING TROUGH TO THE NORTHEAST EARLY NEXT WEEK. ECMWF HINTING
AT POTENTIAL FOR A FRONT TO RIDE INTO THE OHIO VALLEY ON TUESDAY
BUT OP GFS KEEPING THE BOUNDARY FURTHER NORTH. WILL KEEP TUESDAY
DRY AT THIS POINT BUT WILL NEED TO CONSIDER POPS IF MODELS TREND
TOWARDS THE ECMWF SOLUTION IN THE COMING DAYS.

HIGHS RETURN INTO THE LOWER AND MIDDLE 80S DURING THE EXTENDED.
MUCH CLOSER TO AVERAGE HIGHS FOR EARLY AUGUST BUT STILL SLIGHTLY
BELOW NORMAL. UNDERCUT ALLBLEND TEMPS ON OVERNIGHT LOWS BY A
COUPLE DEGREES THROUGH THE PERIOD.

&&

.AVIATION /DISCUSSION FOR 291800Z TAF ISSUANCE/...
ISSUED AT 121 PM EDT TUE JUL 29 2014

VFR CONDITIONS EXPECTED LARGELY THROUGHOUT THE PERIOD.

DESPITE A RELATIVELY SUNNY MORNING...CENTRAL INDIANA REMAINS UNDER
THE INFLUENCE OF AN UPPER TROUGH. A VFR CU FIELD WILL DEVELOP AS
CONVECTIVE TEMPS IN THE 70S ARE REACHED THIS AFTERNOON. WEAK
DISTURBANCE ALOFT DRIFTING INTO THE REGION FROM THE NORTH COMBINED
WITH WEAK INSTABILITY AND STEEP LOW LEVEL LAPSE RATES WILL
CONTRIBUTE TO ISOLATED CONVECTIVE DEVELOPMENT DURING THE LATE
AFTERNOON AND EARLY EVENING...ESPECIALLY AT KIND AND KLAF.
CONFIDENCE IN COVERAGE REMAINS LOW AND WILL KEEP ALL TERMINALS DRY
AT THIS TIME.

CU SHOULD SCATTER TONIGHT WITH REDEVELOPMENT BY MIDDAY WEDNESDAY
AS CONVECTIVE TEMPS ARE AGAIN REACHED. OTHER THAN BRIEF MVFR
VISIBILITIES AT OUTLYING TERMINALS TOWARDS DAYBREAK TUESDAY...
ESPECIALLY KBMG...VFR CONDITIONS WILL BE THE RULE. W/NW WINDS WILL
BE LIGHT TONIGHT AND WEDNESDAY.

&&

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

&&

$$

SYNOPSIS...JK
NEAR TERM...JK
SHORT TERM...JK
LONG TERM....RYAN
AVIATION...RYAN

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