441 
FXUS63 KIND 042017
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
317 PM EST Wed Dec 4 2019

.UPDATE...
The AVIATION Section has been updated below.

&&

.SYNOPSIS...
Issued at 213 AM EST Wed Dec 4 2019

Dry weather is expected today through Thursday as high pressure
over the southern plains slowly pushes toward Indiana and passes
our state to the south by Thursday evening. 

Low pressure passing through the Tennessee river valley may bring
chances for rain to southern central Indiana on late Thursday
night and early Friday morning.

High pressure is then expected to return to Indiana for Saturday
and Sunday. Precipitation chances will once again return early
next work week as a frontal system arrives in the area.

&&

.NEAR TERM /Rest of Today/...

Issued at 1005 AM EST Wed Dec 4 2019

Going forecast is on track and no appreciable changes made. Previous 
discussion follows...

Surface analysis early this morning shows strong high pressure in
place across the southern plains. Deep low pressure was found 
over Ontario. This was resulting continue northwest surface flow 
spilling into Indiana from the upper midwest and Canada. Gulf 
moisture is effectively cut-off. GOES16 shows only a few high 
cloud streaming across Indiana within the flow aloft.

Models continue to suggest NW flow in place across Indiana today
with limited forcing aloft. The high pressure to the southwest is
expected to slowly build eastward. Forecast soundings and time
heights show a dry column with unreachable convective 
temperatures. Thus will continue the trend of partly cloudy skies.
Will not stray far from the NBM on Highs.

&&

.SHORT TERM /Tonight through Friday Night/...

Issued at 213 AM EST Wed Dec 4 2019

GFS and NAM continue to suggest dry weather tonight through
Thursday. The upper flow remains persistent from the 
northwest...resulting in a dry flow of Pacific and Canadian air 
to continue across the area. Forecast soundings and time height
through Thursday continues to reveal a dry column. Thus will 
continue to keep a partly cloudy and dry type forecast through
Thursday...along with temps close to the NBM.

On Thursday night an upper short wave is suggested to push out of
the southern plains toward the deep south. The models suggest a
surface low accompanying this system...along with a diffuse warm
front pushing into southern Indiana. At this point...best moisture
looks to remain south of Indiana...with only limited forcing and
moisture impacting the southern parts of our forecast area.
Forecast soundings show some saturation across the southern parts
of the sate...while soundings remain dry across the northern parts
of the forecast area. Thus will keep some small pops in play
across the Vincennes...Bedford...Seymour areas on late Thursday
night and Friday morning...trending toward a dry forecast across
the north.

By Friday night surface high pressure in place across the upper 
midwest builds southeast into Indiana while the upper wave to the
south quickly exits...progressing to the southeast. Strong
subsidence and drying return to the forecast column on Friday 
afternoon and night. Thus will trend toward a dry forecast 
here...again not straying far from the NBM on temps.

&&

.LONG TERM /Saturday Night through Wednesday/...
Issued at 248 PM EST Wed Dec 4 2019

Ensembles indicate zonal upper flow over the weekend will
transition to a deep trough over the Great Lakes towards the
middle of next week.

At this point, there is a large variance among the individual
members as to the degree and track of the surface development 
associated with the upper trough early next week. Some of the 
members generate a strong surface low, while others indicate a 
relatively flat stable wave rippling along a cold front. This 
probably is a result of questions revolving around phasing with 
some energy in the subtropical jet. 

Will start to bring in PoPs on Sunday, and go with the highest
PoPs on Monday into Monday night, coinciding with the passage of
the surface system. Will keep precipitation type as rain through
Monday, and then transition more towards snow Monday night and 
Tuesday towards the end of the event, as heights and thicknesses 
drop. Potential exists for some snow accumulations Monday night 
into Tuesday. 

&&

.AVIATION /Discussion for the 042100Z KIND TAF Update/...
Issued at 316 PM EST Wed Dec 4 2019

No significant changes made to the forecast at this time. Previous
discussion follows.

Wind gusts of 18 to 27 kts should continue through the afternoon
out of 270 to 300. Gusts will drop off with sunset and winds will
become light overnight. Currently VFR conditions expected with
high pressure building to the south of the sites. Forecast
soundings indicate some potential for patchy fog from 6 to 14Z,
but no other guidance agrees with this so will continue to leave
out at this time.

&&

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

$$

SYNOPSIS...Puma
NEAR TERM...Puma/CP
SHORT TERM...Puma
LONG TERM....JAS
AVIATION...CP/JAS