Lafayette, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

918
FXUS63 KIND 060411
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1211 AM EDT Wed May 6 2026

.KEY MESSAGES...

- Cooler and rainy overnight.

- Heavy rain could result in localized flooding of low lying and
  agricultural areas.

- Largely below normal temperatures this upcoming week, with
  multiple chances for more rain on Friday Night and again on Sunday.

&&

.FORECAST UPDATE...
Issued at 1037 PM EDT Tue May 5 2026

The forecast has been on track this evening as widespread rain
continues for all of Central Indiana. Pulled back the thunder and
lightning threat across most of Central Indiana as local ACARs
soundings indicate an atmospheric profile too stable to support any
lightning activity. Kept an isolated lightning threat for South
Central Indiana from Vincennes to Bloomington to Greensburg and
points south as 100-200 j/kg of CAPE have been enough for several
lightning strikes in stronger showers. However expect lightning to
diminish through the night as colder air behind the front works its
way south and stabilizes the atmosphere.

Rain persists through around 06-08z as most CAMs have been
consistent in showing deep moisture being cut off and the best
forcing for ascent pushing off to the east then. Potential is there
for fog development after the rain ends in the 07-13z timeframe for
portions of Central Indiana. Confidence is low in the occurrence of
fog; however a saturated boundary layer with diminishing winds
during the overnight hours can certainly support fog. Some CAMs does
show surface RH near 100 percent within the Wabash River Valley
toward sunrise, which could be where fog develops. Will watch how
this plays out through the night as lower clouds and some fog may
linger into the morning hours before drier air lifts the cloud deck
and dries the near surface layer.

&&

.DISCUSSION (This evening through Tuesday)...
Issued at 311 PM EDT Tue May 5 2026

Steady rain has overspread much of central Indiana as of 2pm, though
a break in the rain is taking shape towards the Illinois state line.
This should gradually fill in as broad forcing aloft arrives from
the west. Guidance is in excellent agreement showing widespread rain
through the evening and into the overnight. Additionally, some weak
instability may creep far enough north to allow for embedded
convection capable of thunder. Overall, instability is only a couple
hundred J/Kg in the most aggressive solutions...so we will keep the
mention of thunder to a minimum.

Model soundings indicate a fairly deep warm cloud layer (around
10000 feet) with a mostly saturated column. As such, warm rain
processes with abundant moisture (PWATS around 1.25 inches) should
allow for efficient rainfall production today. Any embedded
convective element could allow for rather heavy rainfall rates
despite meager radar appearance. Therefore localized flooding is our
primary hazard today. Flash flooding is less of a concern, as
rainfall rates shouldn`t be high enough for that. Slower inundation
of low-lying areas and roadways is more probable. Most guidance
shows between 1-2 inches of additional rainfall through tonight,
with the highest amounts along and south of I-70.

Tonight

Additionally, winds have turned northerly behind a cold front that
is moving southward this afternoon. Temperatures have dropped around
5 degrees with the frontal passage and a slow drop is expected into
tonight. Lows in the 40s are likely for much of the region by
sunrise Wednesday. Cloud cover will take longer to clear out than
the rain which should help limit radiational cooling. However,
should clearing occur then patchy fog cannot be ruled out.

Wednesday

Partly to mostly cloudy skies prevail on Wednesday within the post-
frontal environment. Temperatures are expected to be cool, roughly
10-15 degrees below average for this time of the year (average highs
in the low 70s). Surface high pressure building in will keep winds
rather light.

Thursday

Surface high pressure is firmly established by Wednesday night, and
ideal radiative cooling conditions look to be present. Clear skies,
light winds, and a subsident atmosphere should promote temperatures
into the upper 30s by sunrise Thursday. Patchy frost and fog may be
possible, mainly in rural areas where cooling potential is greatest.
Light winds and sunny skies will allow for a steep diurnal curve,
with temperatures rebounding nicely to near 60s by the afternoon.

High pressure begins departing to the east Thursday night, allowing
for southwesterly flow to develop. Winds at the surface remain
light, however, under a stable boundary layer. As such, another
night with good radiative cooling potential is likely Thursday
night. Lows in the low 40s appear likely.

Friday onward

Southwesterly flow intensifies on Friday with warmer weather
expected. Highs near 70 return for much of the area. Though low-
level flow is out of the southwest, broad northwesterly upper-level
flow remains in place. Ensemble guidance shows a shortwave trough
diving southeastward late Friday. With little surface reflection,
mass response is limited. Nevertheless, enough moisture should lift
northward to allow for scattered showers and thunderstorms. Model
soundings do not show a lot of instability, a couple hundred J/Kg at
most, but enough for the mention of isolated thunder.

Broad troughing persists into the weekend and potential early next
week. As such, near to below average temperatures are favored.
Ensemble guidance is hinting at a return to a warmer weather pattern
around mid-month, though the signal isn`t very clear at the moment.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 1211 AM EDT Wed May 6 2026

Impacts:

- IFR conditions through much of the overnight.
- Improvement to VFR towards and after 10Z-12Z.
- Rain ends by 14Z with a return to VFR.

Discussion:

Radar shows a continual steady stream of light rain streaming toward
the TAF sites, stretching west to southern MO. This steady stream of
rain will continue to fall across the TAF sites overnight, providing
mainly IFR to MVFR Cigs. Improvement will be at LAF first as the
rain sags southward, with eventual improvement at HUF and IND
followed by BMG.

Forecast soundings today keep at least some mid level cloudiness
across the area through the afternoon and into the evening, however
much of this saturation appears to be at mid, VFR, levels.

Overall, after the front sags southward along with the associated
rain, surface high pressure over the plains will begin to control
our weather and cause a return to VFR.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

UPDATE...CM
AVIATION...Puma
DISCUSSION...Eckhoff