926 
FXUS63 KIND 020859
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
359 AM EST Sat Mar 2 2019

.UPDATE...
The LONG TERM and AVIATION Sections have been updated below.

&&

.SYNOPSIS...
Issued at 300 AM EST Sat Mar 2 2019 

A southern system and upper wave will bring snow to the area late 
tonight and Sunday. Dry but very cold weather will follow in its 
wake as Arctic high pressure builds in next week. Finally, another 
system will bring rain and snow to the area late next week and 
weekend. 

&&

.NEAR TERM...(Today)
Issued at 300 AM EST Sat Mar 2 2019 

Good confidence in dry weather today. A cold front will dissipate as 
it moves across central Indiana today. Meanwhile, fast zonal flow 
will bring plenty of cloud cover over the area per model rh time 
sections and upstream satellite trends.

Low level thermal progs and cloud cover supports near normal blend 
highs in the 40s.

&&

.SHORT TERM...(Tonight through Monday night)
Issued at 300 AM EST Sat Mar 2 2019 

The main concerns for the short term will first of all be snow 
accumulation and then the cold.

The new 00z ECMWF is now in better agreement with the other models 
with the track and strength of a southern stream low pressure 
system. 

GOES-17 was showing an upper system closing in on the northern 
California coast. This system will shear as it moves on shore into 
the fast zonal flow. That said, it will still remain in tact enough 
to spin up a surface low over the southern states on Sunday. All 
models now take the surface low center over northern South Carolina 
and upper trough over the upper Ohio Valley by 00z Monday. 
Meanwhile, a powerful 140 plus knot upper jet will be rounding the 
base of a Hudson Bay vortex. This jet, some insentropic lift on the 
290K level, the upper system and deep moisture will allow for 
widespread snow on Sunday, starting after 06z. Bufkit soundings and 
Forecast Builder suggest some rain could mix in early on and also 
Sunday afternoon. 

WPC QPF along with snow ratios support 1 to 3 inches of total 
snowfall and after coordination matches up with adjacent offices. 
Highest snow amounts should be south of a Tipton to Terre Haute 
line, where the best isentropic lift will be. That said, rain could 
mix in far south as mentioned earlier.

For now, will just be issuing an SPS for the snow and hit hard in 
the HWO.

After that, temperatures will be the main focus as Arctic high 
pressure from the Mountain West to the central Plains allows for 
cold Canadian air to flow in from the southeast. Model rh time 
sections were also showing very dry air, so clear skies combined 
with fresh snow support the well below normal blend temperatures 
with lows in the single digits possible northwest by early Monday 
morning. Highs Monday will only be in the upper teens and middle 
20s, some 20 to 25 degrees below normal. Most areas should see 
single digits Monday night.

&&

.LONG TERM /Tuesday through Friday Night/...

Issued at 320 AM EST Sat Mar 2 2019

The main focus of the long term period will continue to be the
chances for accumulating snow on Thursday and Friday with an upper
trough. But first, dry and cold temperatures will dominate the
forecast from Tuesday through Wednesday. Daytime highs will only
top off in the 20s, about 20 degrees below normal, and overnight
lows will fall into the single digits and teens on Tuesday night
and Wednesday night, respectively.  

As the pattern shifts on Thursday, surface flow will become
southwesterly and warm advection ahead of a surface low over
eastern Oklahoma will help to bump temperatures closer to normal
for Thursday and Friday. Nonetheless, precipitation chances will
also increase as this surface low draws Gulf moisture into central
Indiana ahead of the aforementioned upper trough.  

Precipitation chances will really escalate around Thursday
afternoon from the southwest, spreading across all of central
Indiana by Thursday evening. Right now, confidence is low in where
the rain/snow line will set up, but initially, expect rain to keep
snow totals down on Thursday afternoon. As the temperatures drop
by Thursday evening though, there should be a rather quick shift
to mainly snow with some quick accumulations through Friday
morning before temperatures increase again and snow transitions
back to rain.

&&

.AVIATION /Discussion for the 02/09Z TAF Update/...

Issued at 320 AM EST Sat Mar 2 2019

Update...
No changes.

Previous Discussion...
VFR to start at the sites, with MVFR clouds moving in from the
west/southwest after around 10z at KHUF and the other sites within
a couple hours of that. Ceilings should lift to VFR in the
afternoon. Light and variable winds through the night will shift
to northwesterly around 5 to 10 kts during the day.

&&

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

&&

$$

SYNOPSIS...MK
NEAR TERM...MK
SHORT TERM...MK
LONG TERM....TDUD
AVIATION...CP/TDUD