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fxus63 kind 262034 
afdind

Area forecast discussion
National Weather Service Indianapolis in
334 PM EST sun Feb 26 2017

Update...
the synopsis...near term...short term and aviation sections have
been updated below.

&&

Synopsis...
issued at 332 PM EST sun Feb 26 2017

An active weather pattern is in place with chances for mainly rain
through much of the week, a rain snow mix at times later in the
week, and chances for thunderstorms Tuesday through Wednesday.
Temperatures will warm above normal Monday through Wednesday
before dropping to normal to end the work week.

&&

Near term /tonight/...

Issued at 332 PM EST sun Feb 26 2017

A warm front forming south of the area will bring precipitation
chances to the southern counties tonight. While some isentropic
lift may arrive this evening, dry surface air will take some time
to saturate, and thus don't think the initial lift will result in
much more than an increase in clouds. Have slowly increasing pops
in the south starting around 10 PM, maximizing at around a 40
pop in the southeast at the end of the period. Chances for
measurable rain look confined to generally south of I-70, but
clouds should overspread the entire area.

With the cloud cover, overnight lows should be in the 30s. It
currently looks like even the northern counties will stay above
freezing, but that area may get close. Could see a bit of snow mix
in with the rain on the northern edge of the precip shield, but
do not anticipate any accumulation.

&&

Short term /Monday through Wednesday/...

Issued at 332 PM EST sun Feb 26 2017

Forecast focus is on thunderstorm and severe storm chances Tuesday
through Wednesday. Models have some differences in timing of the
cold frontal passage and this will effect wednesday's forecast.

Monday skies will start out cloudy as the isentropic forcing
slides off to the east and takes small rain chances with it. Some
clearing could move in from the west. Warm advection will allow
temperatures to climb back into the 50s. Monday night a warm front
moves through the area and bring more chances for rain into
Tuesday morning.

By Tuesday afternoon the forecast area is in the warm sector of a
strengthening low pressure system. On Tuesday night the upper
forcing moves into the area, and a low level jet ramps up and
moves overhead. Dynamics look good with this system and
instability will be available, but may be elevated when the best
dynamics are in place and this should help contain severe
potential to some chances for hail and wind. Slight risk from Storm Prediction Center
looks reasonable.

Timing differences in the cold frontal passage shown by the NAM
and GFS will make a difference in whether or not threat for severe
or even thunderstorms is maintained into the afternoon on
Wednesday. For now tried to split the difference and carrying
chances for thunderstorms through the morning with only a slight
chance across the southeastern counties in the early afternoon. If
the front slows down similar to the NAM depiction then chances for
thunder will be greater and there may be some severe potential,
but at this point would lean toward the GFS solution of the faster
passage.

&&

Long term /Wednesday night through Sunday/...
issued at 215 PM EST sun Feb 26 2017

Cold front passing through the Ohio Valley Tuesday night and
Wednesday will be off to the east of the region Wednesday night.
Still enough lingering residual moisture as the colder air spills
in that could see rain mix with or briefly change over to a few
snowflakes before the precipitation ends.

Amplified upper flow pattern setting up for late week with ridging
developing over the western part of the country and a broad trough
downstream over the Great Lakes and Ohio Valley. Weak surface ridging
will provide for a mainly dry and chilly Thursday before a fast
moving Alberta clipper swings through the lower Great Lakes
Thursday night. Precipitation will break out by late day Thursday
and continue Thursday night. Model soundings showing precipitation
likely to begin as rain before transitioning to light snow
Thursday night and early Friday. At this early stage...does appear
could see a very light accumulation in spots over northern
counties by Friday morning.

High pressure will build across the region for Friday and
Saturday with daytime temperatures warming as surface flow swings
around to the southwest as the center of the high passes. The
approach of a frontal boundary from the north by late next
weekend may bring a few showers into the area.

The roller coaster ride with temperatures will continue through
the period. After two cooler days Thursday and Friday with highs
no warmer than the low to mid 40s for most...the return of
southwest winds for the weekend will enable highs to rise into the
60s by Sunday.

&&

Aviation /discussion for 262100z taf issuance/...

Issued at 332 PM EST sun Feb 26 2017

Updated current conditions only. Previous discussion follows...

Winds will gust off and on through the afternoon hours out of the
southwest around 16-24 kts before setting down around sunset. Clouds
will increase through the afternoon and overnight as a low
pressure system moves through south of the sites. MVFR ceilings
could move up from the south as well, arriving at kbmg around 12z
or so and possibly getting up to khuf and kind after that. Don't
think the lower cloud deck will make it as far north as klaf so
left out of there. Could see some rain showers as well at the
southern sites tomorrow morning, but confidence isn't great so
just going with vcsh for a couple hours at khuf and for the
morning at kbmg for now.



&&

Ind watches/warnings/advisories...
none.
&&

$$

Synopsis...cp

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