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fxus63 kind 170220 
afdind

Area forecast discussion
National Weather Service Indianapolis in
920 PM EST Sat Nov 16 2019

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

&&

Synopsis...
issued at 342 PM EST Sat Nov 16 2019

A sharp upper trough will bring a small chance of light
precipitation to all or parts of central Indiana Sunday afternoon
and night. Then, high pressure will bring dry and gradually warmer
weather to the area through Wednesday. After that, another weather
system will bring widespread precipitation to the area Wednesday
night through late Thursday.

The work week and early weekend will start of dry with well below
normal temperatures once again. Yet another system could bring snow
or rain to the area later in the weekend.

&&

Near term...(tonight)
issued at 342 PM EST Sat Nov 16 2019

Could confidence in dry weather tonight with just an increase in mid
and high clouds per model rh time sections as a low pressure system
approaches from the west. With the increased cloud cover,
temperatures should not fall below the lower and middle 20s per the
blend.

&&

Short term...(sunday through tuesday)
issued at 342 PM EST Sat Nov 16 2019

The 12z GFS and 12z European model (ecmwf) were in general agreement that a sharp
upper trough would become negatively tilted as it moves across
central Indiana Sunday night and Monday. Models and model rh time
sections suggest more moisture may be available then previously
thought. So, the blend is trending further east and slightly higher
with pops Sunday night. This looks reasonable and will be accepted.
Buorgouin method and surface temperatures suggest rain will mix with
or change to freezing rain and or snow Sunday night from northwest
to southeast. Could see some rain showers late in the afternoon over
far northwestern parts prior to the changeover.

The upper flow will become zonal in the wake of the system on
Monday, and aside from a very weak Tuesday system, this will support
dry weather and warmer temperatures. That said, model soundings and
time sections suggest low level moisture will be trapped resulting
in lingering cloud cover but closer to normal temperatures in the
middle 40s to around 50 by Tuesday per the blend.

&&

Long term /Tuesday night through Saturday/...

Issued at 229 PM EST Sat Nov 16 2019

Dry weather is expected Tuesday night through early Wednesday
night as an upper ridge moves east across central Indiana. A low
pressure system will approach from the west late Wednesday night
and bring chances for rain to the area. The cold front associated
with this system will move through the area Thursday and rain is
expected across the entire area during the day. Rain will move out
Thursday night. With the falling temperatures in the wake of the
frontal passage, could see a brief rain/snow mix, but think it is
more likely that dry advection will bring an end to the precip
before the cold air arrives. Pretty high confidence in rain
chances Thursday given model agreement, otherwise average
confidence for the rest of the precip chances in the long term.

While high temperatures should climb into the 50s on Wednesday and
Thursday, the cold frontal passage will bring below freezing lows
and highs in the 40s back for the weekend.

&&

Aviation /discussion for the 17/03z taf update/...

Issued at 919 PM EST Sat Nov 16 2019

Update...
no changes.

Previous discussion...
VFR conditions will prevail for the duration of the taf period.
There will be low chances for some rain/snow showers across
northwestern portions of central Indiana tomorrow, but they
shouldn't impact taf sites. Meanwhile, winds will be light and
variable.

&&

Ind watches/warnings/advisories...none.

&&

$$

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