Area Forecast Discussion
Issued by NWS Northern Indiana

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KIWX 022359
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
759 PM EDT THU JUL 2 2015

.SYNOPSIS...
ISSUED AT 758 PM EDT THU JUL 2 2015

HIGH PRESSURE WILL CONTINUE TO DOMINATE ACROSS THE UPPER GREAT
LAKES THROUGH THE HOLIDAY WEEKEND. LOWS OVERNIGHT WILL DIP TO THE
LOWER TO MIDDLE 50S...WITH HIGHS REBOUNDING INTO THE UPPER 70S TO
AROUND 80. THE NEXT CHANCE OF RAIN WILL HOLD OFF UNTIL MONDAY
NIGHT.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 304 PM EDT THU JUL 2 2015

LAKE ERIE MARINE LAYER THAT MOVED IN ON NE FLOW ALONG WITH
DIURNAL CU FIELD HAS A BIT MORE CLOUD COVER THAN PREVIOUSLY
ANTICIPATED...BUT ALL IN ALL A VERY PLEASANT SHORT TERM AS THE
FORECAST AREA FINDS ITSELF NICELY POSITIONED BETWEEN A SPLIT IN
THE MID-UPPER FLOW WITH SURFACE HIGH PRESSURE RIDGE SANDWICHED IN
BETWEEN OVER OUR AREA. NORTHERN WAVE WILL MOVE THROUGH ONTARIO
WHILE SOUTHERN WAVE EXPECTED TO DROP DOWN INTO TN/OH VALLEY AND
RE- INVIGORATE STALLED SURFACE BOUNDARY. THIS MAY PUSH SOME MID-
HIGH CLOUDS UP INTO OUR SOUTHERN CWA ON FRIDAY BUT OTHERWISE COOL
DRY NE/E FLOW FROM SURFACE HIGH PRESSURE WILL DOMINATE WITH TEMPS
5-10F BELOW NORMAL.

&&

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 304 PM EDT THU JUL 2 2015

BY FRIDAY NIGHT LOCAL AREA SHOULD BE POSITIONED BETWEEN SOUTHERN
AND NORTHERN STREAM SHORT WAVES...WITH THE SOUTHERN STREAM WAVE
TRACKING ACROSS THE LOWER OHIO VALLEY. EASTERLY LOW LEVEL FLOW
SHOULD KEEP DRY AIR MASS ANCHORED IN PLACE...WITH ANY PRECIP
CHANCES WITH NORTHERN STREAM WAVE LIKELY TO REMAIN WELL TO THE
NORTH. MID LEVEL RIDGING TO BUILD ACROSS THE OHIO VALLEY/GREAT
LAKES SATURDAY AND SUNDAY WITH QUIET CONDITIONS CONTINUING.
SOMEWHAT AMPLIFIED NATURE OF PATTERN SHOULD ALLOW FOR MAINTENANCE
OF WEAK LOW LEVEL THERMAL TROUGHING THROUGH SUNDAY. A DRY AIR MASS
WILL ALSO REMAIN IN PLACE THROUGH THE WEEKEND VIA EASTERLY LOW
LEVEL FLOW AND BROAD SYNOPTIC SCALE SUBSIDENCE. TEMPERATURES
SHOULD SLOWLY MODERATE THROUGH THE WEEKEND...WITH HIGHS IN THE
LOWER 80S EXPECTED BY SUNDAY.

MAIN ITEM OF INTEREST FOR NEXT WEEK WILL BE EVOLUTION OF UPPER
FORCING AND ASSOCIATED COLD FRONT MONDAY-TUESDAY. FAIRLY ROBUST
MID/UPPER LEVEL RIDGING PRECEDING THIS TROUGH...AND DAMPENING NATURE
OF THE UPPER WAVE AS IT REACHES SOUTHERN ONTARIO CONTINUE TO SUPPORT
SLOWING MODEL TREND OF PAST SEVERAL CYCLES. MORE VEERED LOW LEVEL
FLOW BY LATER MONDAY AND ESPECIALLY ON TUESDAY PRECEDING THE FRONT
SHOULD ALLOW FOR BEST MOISTURE PROFILES OF THE PERIOD AND NOTICEABLY
MORE HUMID CONDITIONS TUESDAY. HAVE MAINTAINED HIGH CHANCE POPS
CENTERED DURING THE DAY TUESDAY...ALTHOUGH SLOWING NATURE OF FRONTAL
BOUNDARY WITH FLOW DEAMPLIFICATION WILL KEEP AT LEAST A THREAT OF
SCATTERED SHOWERS AND STORMS IN THE FORECAST THROUGH MID WEEK. THIS
BOUNDARY MAY GET A REINFORCING PUSH SOUTHWARD AGAIN FOR WEDNESDAY
NIGHT/THURSDAY AS MEDIUM RANGE MODELS POINT TO ANOTHER NORTHERN
STREAM VORT MAX PROGRESSING ACROSS THE GREAT LAKES. SEASONABLE
TEMPERATURES ARE EXPECTED THROUGH THE PERIOD.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 759 PM EDT THU JUL 2 2015

RELATIVELY MUNDANE VFR MET CONDS TO CONT THROUGH THE FORECAST PD
AND BYND. SOME CONCERN WITH LLWS/BLO 1KFT AGL AS EASTERLY FLOW
BEGINS TO RAMP AT BASE OF SUBSIDENCE INVERSION ACRS SRN/CNTL IN
OVERNIGHT...WITH KFWA ON NRN PERIPHERY OF THIS FEATURE. DEGREE OF
PRESENCE/IMPACT HIGHLY DEPENDENT ON DEGREE OF SFC LYR
DECOUPLING. HAVE ADDED FOR NOW GIVEN SHORT TIME DURATION FOR POTNL
ONSET...AND WL CONT TO MONITOR TRENDS SHOULD NEED FOR DELETION
BECOME EVIDENT.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SYNOPSIS...MURPHY
SHORT TERM...JAL
LONG TERM...MARSILI
AVIATION...MURPHY


VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.