Area Forecast Discussion
Issued by NWS Indianapolis, IN

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KIND 182345
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
745 PM EDT Mon Jun 18 2018

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

&&

.SYNOPSIS...
Issued at 338 PM EDT Mon Jun 18 2018

A cold front is expected to drop drop south across central Indiana
Tuesday night into Wednesday before stalling out. This front will
then lift northeast and another cold front will drop southeast over
the area and stall out. These frontal systems will interact with a
warm, moist and unstable airmass and result in periodic unsettled
weather.

The well above normal temperatures will become more normal for this
time of year by Wednesday.

&&

.NEAR TERM /Tonight/...
Issued at 338 PM EDT Mon Jun 18 2018

The heat index and PoPs will be the main concern tonight.

Models in good agreement that the upper ridge will be shunted
southward tonight. This will allow a cold front to approach from the
northeast. This supports small PoPs over our northern half tonight.
In addition, will keep a small chance in over the whole forecast
area through 8 pm, as radar has indicated a couple of isolated cells
that formed from the peak heating this afternoon. High Resolution
Rapid Refresh also supports small PoPs through 8 pm and then small
ones over the northern half later tonight.

The heat index has been on the fringes of advisory criteria through
the afternoon and should be well below by 8 pm, when the Heat
Advisory expires.

&&

.SHORT TERM.../Tuesday through Thursday/...
Issued at 338 PM EDT Mon Jun 18 2016

Unsettled weather will be the main them of the short term.

Latest indications are that as an upper low approaches the Plains,
it will suppress the stubborn upper ridge south to the southeastern
states. This will also allow the cold front to drop south across
central Indiana sometime late Tuesday night through Wednesday night
before it stalls out. The exact timing and location of the front
will make a difference in temperatures. Thus, confidence in
afternoon highs to within a degree or two are low for any one
locale. So, prefer to leave blend temperatures alone.

The front will interact with a warm, moist and unstable airmass and
result in scattered to widespread thunderstorms from Tuesday on.
Could some strong or possibly severe storms on Tuesday afternoon as
the atmosphere becomes moderately to strongly unstable. However,
weal shear suggests only marginally high thunderstorm winds and
marginally large hail in pulse type storms.

&&

.LONG TERM (Thursday night through Monday)...

Issued at 203 PM EDT Mon Jun 18 2018

A stormy period is likely Thursday night into Friday night. After
that the forecast is more uncertain.

The models don`t agree on fine details, but they concur a front
should cause numerous thunderstorms early in the period.  They
disagree on what will happen to the front starting Saturday. For now
the consensus POPs, which are mostly in the chance category, are the
best forecast.

Expect temperatures to be cooler than recently. Readings on a given
day could be either a few degrees above or below average depending
on precipitation and sky cover. Possible errors are 4 degrees.

&&

.AVIATION /Discussion for the 19/00Z TAF Issuance/...

Issued at 725 PM EDT Mon Jun 18 2018

VFR will generally be the prevailing flight category. However, as
showers and thunderstorms enter KLAF and KIND tonight/tomorrow
morning with a cold front, conditions could quickly deteriorate in
any heavy rain showers. Meanwhile, winds will be
west/southwesterly at 5 to 11 kts, and breezy through this evening
with some 20 kt gusts.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM EDT this evening for INZ021-028>031-
035>049-051>057-060>065-067>072.

&&

$$

SYNOPSIS...MK
NEAR TERM...MK
SHORT TERM...MK
LONG TERM....JK
AVIATION...TDUD


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.