000 
fxus63 kind 192310 
afdind 


Area forecast discussion 
National Weather Service Indianapolis in 
610 PM EST sun Feb 19 2017 


Update... 
the aviation section has been updated below. 


&& 


Synopsis... 
issued at 221 PM EST sun Feb 19 2017 


A weakening cold front is expected to move through the area Monday 
night into Tuesday morning. A stronger low pressure system may 
affect the area towards the later parts of the week. 


&& 


Near term /tonight/... 
issued at 221 PM EST sun Feb 19 2017 


Dry weather expected tonight as surface ridge drifts off to the 
east. Synoptic pattern favorable for the development of low 
clouds/fog again later tonight, given a light gradient and the 
potential for residual moisture to get trapped under a shallow low 
level inversion. 


Low level thicknesses suggest the GFS MOS lows for tonight look 
reasonable for the most part, so any adjustments will be minor. 


&& 


Short term /Monday through Wednesday/... 
issued at 221 PM EST sun Feb 19 2017 


Lingering fog early Monday morning should burn off by the mid to 
late morning hours Monday. 


Model data suggest a short wave trough will push through the Great 
Lakes region Monday night and Tuesday, dragging a weakening cold 
front through the local area. Appears there may a decent amount of 
lift, albeit rather narrow, for a precipitation threat late Monday 
night into Tuesday morning over the northern zones. Will go with 
pops starting Monday night and continuing through early Tuesday 
evening to cover the passage of this system, with the highest pops 
coinciding with the best lift. 


Some weak elevated instability may be associated with this feature 
as well, but convective parameters not very impressive at this 
point. 


Will go with a dry forecast by Wednesday as upper flow becomes zonal 
in the wake of short wave trough, and weak surface high pressure 
develops over the area. 


Progged low level thicknesses suggest the GFS MOS highs for Monday 
may be on the cool side. Will nudge the guidance highs up a bit in 
that period. The remainder of the periods look OK for now. 


&& 


Long term.../Wednesday night through Sunday/... 
issued at 225 PM EST Mon Feb 19 2017 


The highlights of the long term will be warm weather for the 
remainder of next week with a return to seasonable temperatures by 
Saturday. In addition, unsettled weather is on tap late week with 
strong storms possible Friday. 


Models are having temporal and spacial issues with a potent system 
that will be developing over The Rockies midweek and lifting 
northeast across the plains and then Great Lakes late week and into 
the weekend. Thus, confidence in timing and coverage of looming 
convection is not great and will accept the superblend which has the 
highest pops Friday afternoon and evening and is dry by Saturday. 
Prior to that, a front will drop southeast over the area before 
lifting back to the north Thursday and Thursday night. Superblend 
output has small pops over all or parts of the area by Wednesday 
night. 


Model instability progs support thunder chances Thursday afternoon 
through Friday. Adjacent offices agreed through coordination. With 
such strong dynamics and some instability...day6 Storm Prediction Center outlook 
supports severe possibility with mainly a damaging wind threat. 


Low level thermal progs and expected cloud cover support well above 
normal blend temperatures in the mid 60s to around 70 through Friday 
and more seasonable highs mostly in the 40s by Saturday in the wake 
of the cold front. 


&& 


Aviation /discussion for 200000z taf issuance/... 
issued at 610 PM EST sun Feb 19 2017 


Restrictions are likely to develop again tonight and early Monday 
in fog and low stratus with a return to VFR conditions for the 
afternoon. 


Low stratus from earlier had completely diminished over the region 
with just wisps of mid and high level clouds drifting across 
central Indiana. Do expect a return of the lower stratus later 
this evening and into the overnight along with an expansion of fog 
as model soundings once again show the development of a shallow 
but sharp inversion as the upper level ridge sets up just west of 
the area. Presence of the inversion near or just below 1000ft is 
lower than the inversion set up Saturday night...and may see more 
impacts from fog versus low stratus late tonight as a result. 


Introduce sub-IFR conditions after 06z through mid morning Monday 
before increased low level mixing weakens the inversion. Potential 
is there for patchy dense fog but overall...appears hi-res 
guidance is again overdoing the extent for dense fog. Have tapered 
back a bit and will adjust as the fog and stratus develops if need 
be. 


Once the fog and stratus dissipates near midday Monday...expect 
partly cloudy skies for the remainder of the day with southeast 
winds generally less than 10kts. Likely to see an increase in 
cloud cover by Monday evening in advance of the approaching front 
from the west. 




&& 


Ind watches/warnings/advisories...none. 


&& 


$$ 


Synopsis...jas 



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 2017
The Weather Company, LLC