Area forecast discussion 
National Weather Service Indianapolis in 
438 PM EDT Thursday Oct 8 2015 

the aviation section has been updated below. 


issued at 148 PM EDT Thursday Oct 8 2015 

A cold front over the upper Midwest will sweep across Illinois and 
Indiana on Friday morning...before departing by Friday afternoon. 
This will result in clouds along with chances for some light rain 
showers to central Indiana...particularly late tonight and early 
on Friday morning. 

Cool high pressure is then expected to build across the Ohio 
Valley through the rest of the weekend...providing dry weather 
along with near normal temperatures. A warm front will approach 
the area on Monday and Monday night and bringing our next best 
chance for showers. After that...dry Fall weather is expected much 
of the next work week. 


Near term /tonight/... 

Issued at 148 PM EDT Thursday Oct 8 2015 

Surface analysis early this afternoon shows low pressure in place 
over Wisconsin and Minnesota. Indiana ws in the warm sector of 
this system...experiencing warm southwest surface flow. Scattered-broken 
cloud was seen across the state on visible images. National radar 
mosaics show some precipitation ahead of a cold front accompanying the 
low...over Michigan and eastern Wisconsin. 

Main forecast challenge today will be probability of precipitation. 

GFS and NAM both agree that the cold front will push toward 
Indiana late tonight. However...moisture and forcing remain a 
problem. Forecast soundings fail to show deep moisture as do the 
time height sections. GFS and NAM depict a broad short wave 
aloft...with best forcing over the Great Lakes. Decent lower level 
convergence remains in place. Given this...some the low chance probability of precipitation 
seem warranted...but mainly across the northern parts of the 
forecast area and mainly after 09z...very late. Given the expected 
increasing clouds and broad warm air advection in place 
overnight...will trend lows at or above mavmos at most spots. 


Short term /Friday through Sunday/... 

Issued at 148 PM EDT Thursday Oct 8 2015 

GFS and NAM suggest the previously mentioned cold front will be 
exiting the area during the morning hours on Friday. Best moisture 
and forcing remains to be seen across the northern and eastern 
parts of the forecast area. Forecast soundings continue to show 
some lower level moisture during the morning hours. After 
18z...GFS and NAM depict good middle level subsidence as the front 
dives southeast. Thus will trend toward low chances for morning 
rain...mainly across the north and east...then trend toward a dry 
forecast after lunch. Forecast soundings suggest cold air 
advection along with some trapped SC in the wake of the front on 
Friday afternoon. Thus not much clearing will be expected until 
later in the afternoon. Thus will trend highs at or below mavmos 

Strong high pressure then is expected to settle across the region 
through the rest of the weekend. Models show strong subsidence in 
place along a dry column and unreachable convective temperatures. Thus 
will expected mostly clear nights and mostly sunny days on Friday 
night through Sunday. Good cold air advection remains in place on 
Friday night and Saturday...thus will trend lows at or below 
mavmos. Due to good radiational cooling effects on Saturday night 
will trend lows at or below mavmos then. Warm air advection and 
full sun expected on well as the lower level flow 
turning more west to southwesterly. Will trend highs warmer than 
mexmos here. 


Long term /Sunday night through Thursday/... 
issued at 226 PM EDT Thursday Oct 8 2015 

Models are close enough that the superblend initialization was accepted 
for most items. 

A cold front will move through on Monday...but the front will not 
have a lot of moisture to work with. Thus will keep superblend 
slight chance probability of precipitation most areas. 

Afterward...a dry atmosphere should keep rain at Bay even with some 
weak fronts moving through. /Although will have to keep an eye on 
Thursday as several GFS ensemble members are showing a rain threat/. 

Temperatures will remain near to above average through the period. 


Aviation /discussion for the 082100z ind taf update/... 

Issued at 438 PM EDT Thursday Oct 8 2015 

No changes to the taf. 

Previous discussion follows... 

Issued at 104 PM EDT Thursday Oct 8 2015 

VFR conditions expected through first half of the period...then MVFR 
for second half. 

Scattered cumulus and broken middle cloud will continue through the 
afternoon. Winds could gust to around 15kt. 

Scattered showers will move in late this evening and overnight then 
continue through Friday morning as a cold front moves into and 
through the area. Will use vcsh since showers will be scattered. 

Expect MVFR ceilings to move in behind the front and persist into at 
least early Friday afternoon. 


Ind watches/warnings/advisories... 


near term...puma 
short term...puma 
long term...50 

National Weather Service Glossary of Abbreviations
Back to forecast page
Non-Expanded Version (with abbreviations)

Units: English | Metric

Find the Weather for any City, State or Zipcode, or Country:

U.S. State List | Severe Weather | Tropical Storms | Ski Conditions
United States | Canada | Central America | South America | Asia | Europe | Australia | Africa | Islands

Weather Underground Copyright© 2015
Weather Underground, Inc.

Questions or Comments? Contact Us