Martin, Illinois Weather Forecast Discussion

684
FXUS63 KILX 122313
AFDILX
Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
613 PM CDT Fri Sep 12 2025
.KEY MESSAGES...
- An extended period of well above normal temperatures continues
  across central and southeast IL through next Friday with highs
  in the upper 80s to mid 90s expected through at least Thursday.
- Isolated showers and thunderstorms are possible north of I-74
  overnight. There is a 20-40% chance of showers and thunderstorms
  thunderstorms northeast of a Peoria to Terre Haute line on
  Saturday and along and east of highway 51 during Saturday
  night. Otherwise much of area will see dry conditions into the
  middle of next week.
&&
.DISCUSSION...
Issued at 245 PM CDT Fri Sep 12 2025
A warm front was over central Iowa and northeast MO, just sw of
IL at mid afternoon. Partly to mostly sunny skies prevailed over
central and southeast IL with more scattered cumulus clouds in
eastern IL east of highway 51, along with some passing cirrus
clouds. Warm temps were in the mid to upper 80s with Pittsfield
91F and Quincy 90F. Dewpoints were mostly in the 50s with
dewpoints around 60F in west central IL and at Olney. PW values
had risen to 1.2-1.4 inches in west central IL closer to
approaching warm front. Nearest convection was over central IA
and few isolated cells in north central MO.
Latest CAMs show most of convection tonight to be focused over
the upper MS river valley on nose of low level jet as warm front
lifts ne across central IL during late evening and overnight. But
some CAM members like HRRR and FV3 show isolated convection
dropping se toward I-74 late tonight. So added slight pops mainly
after 2 am tonight north of I-74. CAMs have trended further south
with a cluster of convection dropping SSE into northeast and east
central IL on Sat morning as it weakens. Could see isolated
convection develop along lingering outflow boundaries during Sat
afternoon further south into central IL as MUCAPEs rise to
1500-3000 j/kg and 0-6 km bulk shear values are 25-30 kts in
ne/eastern CWA. More clusters of convection projected to drop
southward over IN and possibly into eastern IL, especially east of
I-57 during Sat night especially overnight hours. SPC added
marginal risk of severe storms for wind and hail ne of a Henry to
Bloomington to Charleston line on Saturday and Sat night.
Lows overnight in the low to mid 60s with areas near the Indiana
border around 60F. Highs Sat in the upper 80s and lower 90s,
coolest ne CWA and warmest from Springfield SW where highs
approaching 95F. Highs in the low to mid 90s on Sunday with mid
90s more common especially from I-57 west where more sunshine
expected. Heat indices to peak around 100F Sunday afternoon over
the IL river valley where dewpoints reach upper 60s to near 70F.
A strong subtropical upper level ridge extending from Texas into
the central/eastern Plains will be over IL from this weekend into
middle of next week, keeping it hot with highs in the low to mid
90s Mon through Wed and upper 80s/lower 90s Thu. Convection
chances will be low Sunday through Wed night, with some uptick in
convection chances Thu/Fri as upper level trof approaches from the
west.
The Climate Prediction Center (CPC) 6-10 Day outlook for Sep 18-22
has 60-70% chance of above normal temperatures over central/se IL.
CPC 8-14 Day Outlook for Sep 20-26 has 55-60% chance of above
normal temps over central/southeast IL. So the late summer heat
looks to continue for awhile.
07
&&
.AVIATION...  (For the 00z TAFs through 00z Saturday Evening)
Issued at 613 PM CDT Fri Sep 12 2025
VFR conditions are expected to continue through the period. Some
light rain showers are present across eastern Iowa late this
afternoon, and there is a low chance these reach KPIA during the
first few hours of the period, but felt it was too unlikely to
warrant a VCSH mention. The other main concern this TAF period is
shower chances overnight into the day Saturday. These will mainly
be focused northeast of the area, but could impact KBMI/KCMI.
Maintained a VCSH mention for now, but this could be removed in
later updates. Some thunder is possible Sat PM, but odds were too
low to warrant a PROB30 group. Winds will be southeasterly
overnight, then southerly or south-southwesterly during the day
Saturday.
Erwin
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$

NWS ILX Office Area Forecast Discussion