NWS Forecast for O'Hare International Airport Chicago, IL Last Update: 7:06 am CST Nov 6, 2024
Be on the lookout for the possibility of fog developing overnight Wednesday/Thursday (not in the forecast yet).
Wednesday Night: Mostly cloudy, with a low around 43. North wind around 5 mph.
Thursday: Mostly sunny, with a high near 58. West northwest wind around 5 mph.
Thursday Night: Mostly clear, with a low around 40. West wind around 5 mph.
Friday: Sunny, with a high near 59. West wind around 5 mph, with gusts as high as 10 mph.
Friday Night: Partly cloudy, with a low around 42.
Saturday: A 40 percent chance of showers after noon. Partly sunny, with a high near 59.
Saturday Night: Showers. Mostly cloudy, with a low around 51.
Sunday: A chance of showers before noon. Partly sunny, with a high near 62.
Sunday Night: Partly cloudy, with a low around 46. Veterans Day: Mostly sunny, with a high near 60.
Monday Night: Partly cloudy, with a low around 44.
Tuesday: Mostly sunny, with a high near 64.
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
537 AM CST Wed Nov 6 2024
.KEY MESSAGES...
- Cooler conditions to close out the week.
- The next potential for rain arrives late Saturday into early Sunday.
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.DISCUSSION... Issued at 141 AM CST Wed Nov 6 2024
Through Thursday:
A cold front is pressing through the region early this morning, resulting in a west-northwest wind shift and falling air and dewpoint temperatures. Fairly extensive post-frontal stratus is evident on nighttime microphysics RGB imagery upstream, and forecast soundings suggest that this cloud cover will continue eastward this morning, resulting in generally mostly cloudy conditions today. This will mute the diurnal temperature rise today, with highs ranging from the low 50s across our northwest, to upper 50s south and east of I-57.
A secondary cold front/trough axis, which is currently pushing through northern Wisconsin, will drop down the lake this afternoon, eventually pushing into northeast Illinois and northwest Indiana by early this evening. Hi-res guidance suggests some potential for some light precip with this boundary, although forecast soundings reveal a pretty shallow saturated layer under a subsidence inversion. As a result, elected simply to nudge some "silent" PoPs up towards 10-15 percent late this afternoon and into the evening, with some potential the day shift will need to consider adding some formal chances for showers.
For tonight into Thursday morning, most guidance suggests lingering post-frontal stratus will erode, although it seems likely that some lake effect cloud cover will remain in place across parts of northwest Indiana. This may set the stage for some fog development (which is currently quite extensive across western Iowa). That said, model forecast soundings depict a bit of flow lingering in the lowest 100 mb, so while clearing skies and temperatures falling towards their crossovers, as well moist grounds would otherwise support a slam dunk in favor of widespread fog development, this casts some increased uncertainty on this potential.
Thursday looks like a nice day as an elongated region of high pressure builds overhead. Some guidance (HRRR/RAP in particular) attempts to build in another region of stratus through the day, although this isn`t currently the most likely solution.
- Carlaw/NWS
Thursday Night through Tuesday:
Overall, no significant changes to the extended time period. Light winds and expected mainly clear skies will likely allow for some patchy/shallow ground fog early Friday morning and have maintained previous mention, though overall confidence is low.
Friday and Friday night are expected to be dry as the next storm system develops in the Plains and lifts northeast to the western Great Lakes Saturday night and Sunday. There is still some uncertainty for precip timing which seem to change with each model run. Currently Saturday afternoon into Saturday evening appears to be the best time window and the precip may end u Pbeing fairly progressive with perhaps a short duration though a bit early for those specifics. Thunder potential also seems to fluctuate with model runs but still possible. There may be some lingering showers on Sunday, mainly across the northern cwa but dry weather is the expected through Tuesday with precip chances returning Tuesday night into Wednesday.
Temperatures are expected to be near or above normal through the period with lows Saturday night/Sunday morning likely in the 40s, perhaps even lower 50s. Sunday may be the warmest day with highs in the lower/mid 60s with breezy southwest winds gusting to 30 mph. cms
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.AVIATION /12Z TAFS THROUGH 18Z THURSDAY/... Issued at 537 AM CST Wed Nov 6 2024
Forecast concerns include...
Mvfr cigs through this evening. North/northeast winds late this afternoon into this evening.
Mvfr cigs are expected to continue into this evening, slowly lifting and possibly into low vfr this evening, though mvfr cigs may continue tonight, especially near Lake Michigan.
Northwest winds around 10kt will turn more northerly this afternoon with speeds diminishing under 10kts by evening, when directions will turn northerly. Its possible wind directions may become north/northeast for a few hours before turning back to the northwest later tonight. cms
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.LOT WATCHES/WARNINGS/ADVISORIES... IL...None. IN...None. LM...None.
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