Area Forecast Discussion
Issued by NWS Indianapolis, IN

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000
FXUS63 KIND 070546
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
146 AM EDT TUE JUL 7 2015

.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED BELOW.

&&

.SYNOPSIS...
ISSUED AT 146 AM EDT TUE JUL 7 2015

A WET COUPLE OF DAYS ARE IN STORE THROUGH THE MIDDLE OF THE WORK
WEEK. A COLD FRONT OVER ILLINOIS AND MISSOURI WILL PUSH EAST AND
STALL OVER INDIANA...BRINGING CHANCES FOR SHOWERS AND
THUNDERSTORMS TODAY AND TONIGHT.

ON WEDNESDAY AND THURSDAY...THE STALLED FRONT WILL LINGER ACROSS
CENTRAL INDIANA. MEANWHILE A COUPLE AREAS OF LOW PRESSURE WILL
PUSH ACROSS INDIANA ALONG THE FRONT. THESE TWO SYSTEMS WILL
CONTINUE TO PROVIDE MORE CHANCES FOR SHOWERS AND THUNDERSTORMS.

HIGH PRESSURE WILL BEGIN TO BUILD ACROSS INDIANA ON THURSDAY
NIGHT IN TO FRIDAY...PUSHING THE FRONTAL BOUNDARY TO THE SOUTHEAST
AND BRING DRIER BUT WARM AND HUMID WEATHER BACK TO INDIANA TO
START THE WEEKEND.

&&

.NEAR TERM /TODAY/...

ISSUED AT 146 AM EDT TUE JUL 7 2015

SURFACE ANALYSIS EARLY THIS MORNING SHOWS A COLD FRONT STRETCHING
FROM NE ILLINOIS TO NORTHEAST MISSOURI AND SOUTHEAST KANSAS. RADAR
SHOW DECAYING SHOWERS AND STORMS ALONG THE FRONT...SLOWLY PUSHING
EAST. IR IMAGERY SHOWS WARMING TOPS. WARM AND HUMID SOUTHERLY FLOW
WAS IN PLACE ACROSS CENTRAL INDIANA WITH DEW POINT TEMPERATURES
IN THE UPPER 60S AND LOWER 70S.

MAIN CHALLENGE TODAY WILL BE POPS. GFS AND NAM SUGGEST THE COLD
FRONT AND ASSOCIATED MOISTURE SHOULD BEGIN TO ARRIVE AT IN THE
AREA BY MID MORNING. FORECAST SOUNDINGS SHOW DEEP SATURATION BY
18Z...WITH PRECIPITABLE WATER VALUES OVER 2 INCHES. EVEN SOME CAPE
AVAILABLE AS CONVECTIVE ARE ONLY IN THE MIDDLE 70S. EXCELLENT
LOWER LEVEL CONVERGENCE IN PLACE AS SEEN BY THE LOWER LEVEL Q
VECTORS. THUS WITH PLENTY OF MOISTURE AND GOOD FORCING...CANNOT
FIND ANY REASON NOT TO HAVE POPS AT 90 OR HIGHER. WILL TRY TO
TREND HIGHEST POPS TO THE MID DAY AND AFTERNOON HOURS...WHEN THE
BEST FORCING LOOKS TO BE IN PLACE.

AS FOR TEMPS WILL TREND HIGHS AT OR BELOW MAVMOS GIVEN THE
EXPECTED CLOUDS AND RAIN.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...

ISSUED AT 146 AM EDT TUE JUL 7 2015

MODELS ARE IN PRETTY GOOD AGREEMENT THE AS THE FRONTAL BOUNDARY
MOVES EAST...IT WILL BECOME ELONGATED AND MORE EAST-WEST ORIENTED
AS IT STALLS ACROSS INDIANA. THUS IT WILL BECOME THE FOCAL AREA
THROUGH THIS PERIOD FOR LOWER LEVEL CONVERGENCE AND PRECIPITATION.
FORECAST SOUNDINGS THROUGH MID DAY THURSDAY REMAIN RELATIVELY
SATURATED...WITH PRECIPITABLE WATER IN EXCESS OF 1.80 INCHES
THROUGH THE PERIOD. TIME HEIGHTS ALSO SHOW DEEP MOISTURE. THUS WE
WILL JUST NEED TO LOOK FOR A FORCING MECHANISM.

FIRST OFF WE HAVE DAYTIME HEATING AVAILABLE FOR US. CONVECTIVE
TEMPERATURES EACH DAY ARE VERY ATTAINABLE...IN THE 70S ON BOTH
WEDNESDAY AND AGAIN THURSDAY. THUS ANY HEATING SHOULD ALLOW PRECIP
DEVELOPMENT. ALOFT THE GFS DEPICTS A SHORT WAVE PUSHING THROUGH
INDIANA OVER THE FRONT ON TUESDAY NIGHT AND A SECOND SHORT WAVE
PUSHING ACROSS THE AREA ON WEDNESDAY NIGHT. NAM IS SLIGHTLY
DIFFERENT WITH ORIENTATION OF THE SHORT WAVE AND THE
TIMING...BUT NONETHELESS...FORCING APPEARS HEADED OUR WAY THE
NEXT COUPLE OF DAY. THUS OUR EQUATION IS NOW

MOISTURE + FORCING = HIGH RAIN CHANCES.

WILL TREND POPS THROUGH THE PERIOD AT OR ABOVE MAVMOS
VALUES...TRENDING HIGHEST POPS DURING THE PERIODS ON TUESDAY
NIGHT AND AGAIN ON WEDNESDAY NIGHT AS THE GFS SHOW BEST FORCING
PUSHING ACROSS THE AREA AT THAT TIME.

AS FOR TEMPS...WITH CLOUDS AND RAIN EXPECTED WILL TREND LOW WARMER
THAN MAVMOS AND TREND HIGHS COOLER.

BEST FORCING APPEARS TO DEPART ON THURSDAY AFTERNOON AND THURSDAY
NIGHT IN THE WAKE OF THE SECOND SHORT WAVE. FORECAST SOUNDINGS
BEGIN TO DRY OUT AT THAT TIME AND PRECIPITABLE WATER MANAGES TO
FALL TO LESS THAN 1.50 INCHES. WILL TREND POPS LOWER AT THAT TIME.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...

ISSUED AT 240 PM EDT MON JUL 6 2015

STRONG UPPER RIDGE WILL RETROGRADE FROM THE SOUTHEAST U S BACK
INTO THE ROCKIES THROUGHOUT THE EXTENDED RESULTING IN A SHIFT FROM
ZONAL FLOW ALOFT TO A MUCH MORE BLOCKY REGIME. WITH A FRONTAL
BOUNDARY OSCILLATING OVER THE REGION...PERIODIC STORMS WITH A
VERY WARM...MUGGY AIRMASS CAN BE EXPECTED THROUGH EARLY NEXT WEEK.

ECMWF CONTINUES TO TREND TOWARDS MODEL CONSENSUS IN TIMING THE
WESTWARD SHIFT TO THE UPPER RIDGE OVER THE WEEKEND. THE FRONTAL
BOUNDARY WILL MOVE NORTH INTO THE LOWER GREAT LAKES IN RESPONSE TO
THE MOVEMENT OF THE RIDGE WITH HEIGHT RISES OVER THE OHIO VALLEY.
WILL KEEP LOWER POPS PRIMARILY OVER FAR NORTHERN PORTIONS OF THE
FORECAST AREA SATURDAY AND SUNDAY.

AS THE RIDGE AXIS REESTABLISHES OVER THE ROCKIES AND HIGH
PLAINS...STRONGER WAVE RIDING UP AND OVER THE RIDGE WILL DIVE
INTO THE REGION SUNDAY NIGHT AND MONDAY AS HEIGHTS ALOFT BUCKLE.
AT FIRST GLANCE...THIS MAY END UP BEING THE BEST CHANCE DURING THE
EXTENDED FOR MORE ROBUST CONVECTION IN THE FORM OF AN MCS TO
IMPACT CENTRAL INDIANA. WILL BUMP UP TO HIGH CHANCE POPS SUNDAY
NIGHT AND MONDAY.

WITH THE FRONT TO THE NORTH OVER THE WEEKEND EXPECT HIGHS
MAINLY IN THE UPPER 80S...WITH LOWER 90S LIKELY CONFINED TO JUST
THE FAR SOUTHERN COUNTIES. TEMPS WILL FALL BACK INTO THE LOWER/MID
80S MONDAY WITH THE ARRIVAL OF THE AFOREMENTIONED WAVE.

&&

.AVIATION /DISCUSSION FOR THE 07/06Z TAFS/...

ISSUED AT 1227 AM EDT TUE JUL 7 2015

MAINLY VFR THROUGH THE NIGHT WITH MVFR CEILINGS DEVELOPING DURING
TUESDAY MORNING AS A FRONTAL BOUNDARY AND SHOWERS MOVE INTO THE AREA.

FRONT WILL PUSH INTO THE AREA LATE TONIGHT INTO TUESDAY AND EXPECT
WIDESPREAD SHOWERS AND PERHAPS A FEW THUNDERSTORMS ALONG IT.
HOWEVER...BARRING MORE EXTENSIVE THUNDER COVERAGE HAVE CHOSEN TO GO
WITH SHOWERS FOR NOW AND A VICINITY THUNDER MENTION.

MVFR CEILINGS WILL ACCOMPANY THE SHOWERS AND WILL LIKELY PERSIST
MUCH OF THE REST OF THE PERIOD.

WINDS WILL GENERALLY BE 10KT OR BELOW...SOUTHWESTERLY BEFORE THE
FRONT AND BECOMING NORTHWESTERLY AFTER FRONTAL PASSAGE.


&&

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

$$

SYNOPSIS...PUMA
NEAR TERM...PUMA
SHORT TERM...PUMA
LONG TERM....RYAN
AVIATION...NIELD

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