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fxus63 kind 261713 
afdind

Area forecast discussion
National Weather Service Indianapolis in
113 PM EDT Mon Jun 26 2017

Update...

The aviation section has been updated below.

&&

Synopsis...
issued at 355 am EDT Mon Jun 26 2017

A strong upper trough over the Great Lakes will produce cooler than
normal weather next few days as it moves slowly to the east. An
upper level disturbance will move east across central and southern
Indiana late today and tonight producing a few showers and
thundershowers. Otherwise...high pressure will dominate our
weather as it moves east across the Ohio Valley.

Warmer and more humid weather will occur after midweek. A frontal
system will become stalled from the Central Plains to southern
Great Lakes and a couple of upper disturbances will result in a
chance of thunderstorms Thursday into Saturday.

&&

Near term /today and tonight/...
issued at 355 am EDT Mon Jun 26 2017

Satellite indicated clear skies were occurring across Indiana and
most of Illinois. An area of low pressure was over the northern
Great Lakes while high pressure was located over southern Missouri
and the northern plains. An upper level weather disturbance was
producing a few showers and thunderstorms over western Iowa and
extreme southeast South Dakota.

This morning will start out mostly sunny and cool with increasing
afternoon clouds. High resolution models indicate little or no
convection will occur until 20z or 21z. Will go with low chance
probability of precipitation after that mainly late this afternoon into tonight.

Mu CAPES about 400 to 700 j/kg and this should be enough for a
few thundershowers late this afternoon and early tonight...I
do not expect any of these to be severe.

Models have trended a little slower in spreading showers into our
area late today and then ending them later tonight. They also
indicate a little more quantitative precipitation forecast over southern sections tonight.
Will go with chance probability of precipitation tonight and gradually ending from the north
overnight.

Models indicate 850 mb temperatures will average +6 to +7 celsius
over northern sections and +10 in the south. This will translate to
highs in the lower 70s over north and central sections and middle
70s over southern sections. Lows tonight will range from upper 40s
far north to middle to upper 50s south. Raised temperatures
slightly over southern sections...otherwise stayed close to a MOS
blend on temperatures.

&&

Short term /Tuesday through Wednesday night/...
issued at 355 am EDT Mon Jun 26 2017

Mostly clear and quiet weather will occur Tuesday and Wednesday
as high pressure moves into the Ohio Valley Tuesday and on to the
east Wednesday. The upper trough will move on to the east and
temperatures will become a little warmer by Wednesday.

Highs will be in the middle to upper 70s Tuesday and lower 80s
Wednesday with some middle 80s southwest. Lows will be in the
middle 50s Tuesday night and middle to upper 60s Wednesday night.

Increasing moisture and an approaching upper disturbance will
result in a chance of showers and few thunderstorms late Wednesday
night over all but far southeast sections. Stayed close to
superblend probability of precipitation and temperatures most periods.

&&

Long term /Thursday through Sunday/...
issued at 355 am EDT Mon Jun 26 2017

The pattern will become rather active early in the extended period.
Wednesday night, a low pressure system is progged to move into the
Great Lakes region. The highest precipitation chances will initially
be over the northern half of central Indiana, but shower and
thunderstorm chances will spread across the entire forecast area by
Thursday morning. Disturbances both at the surface and aloft will
keep showers and thunderstorms in the forecast through the remainder
of the forecast period with the highest chances from Thursday night
through Friday. After that, only low precipitation chances will
continue through the weekend. Meanwhile, temperatures through the
period will be at or just slightly below normal with highs in the
low to mid 80s and lows in the 60s.

&&

Aviation /discussion for the 26/18z tafs/...
issued at 113 PM EDT Mon Jun 26 2017

VFR through the period.

Some spotty showers and perhaps a thunderstorm are possible this
afternoon as an upper level trough moves through the region.
Thunder is a non zero threat, but too low probability for mention.
Will include vcsh around most likely time for showers.

Winds will generally be west/northwesterly with a few gusts to
18-21kt possible during the first 6 hours or so of the period.
Winds will drop below 10kt overnight and become a bit more
northwesterly.

No significant obstructions to visibility are anticipated. A light
patch of fog cannot be entirely ruled out where rain falls, but
predictability of this at a specific point is basically nil at the
moment.

&&

Ind watches/warnings/advisories...none.

&&

$$

Synopsis...jh

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