Our high yesterday was 42° and the low was 18° with mostly sunny skies. Today will feature another sunny day with temperatures reaching into the low 40s to help continue our snow melt.
-- Areas of freezing fog this morning...Dry into Wed -- Latest IR satellite imagery and surface obs indicate extensive stratocumulus over central/northern Lower MI as of 08z. Little additional southward advance of these clouds is expected, and short-range guidance suggests that southerly cloud-layer flow will become established as the morning progresses in conjunction with modest surface pressure falls occuring west of the region. South of this cloudiness, clear skies and light surface winds over much of the forecast area will foster areas of freezing fog this morning as strong radiational surface cooling continues. Some icy/slick spots will be possible on roads this morning, particularly on bridges/overpasses. Patchy freezing fog will again be possible tonight/Wed morning in similarly favorable conditions. Otherwise, dry conditions will prevail into Wed. A shortwave trough/vort max--currently evident in WV imagery near ND/Manitoba-- will glance the area this afternoon/evening and provide modest forcing for ascent, but dry profiles will keep precip well north of the forecast area. -- Thanksgiving Day through Sun -- Global ensemble guidance continues to indicate that an upper ridge over the Pacific NW / northern Rockies will amplify on Wed/Thu, ultimately undergoing anticyclonic Rossby-wave breaking into Fri. Southward of this folding-over ridge axis, an upper trough will dig across the Rockies on Wed, then deepen into a closed/cutoff low near NM/TX on Thu/Fri. Ensemble guidance continues to exhibit appreciable uncertainty regarding the subsequent evolution of this upper low into the weekend, with (1) large values of normalized spread in the 500-mb height field, and (2) poor run-to-run consistency in the ensemble-mean placement of this feature in both EPS and GEFS runs. This uncertainty notwithstanding, the most recent EPS/GEFS means have trended notably slower with the northeastward advance of this feature into Sun. Altogether, there appears to be two timeframes during which precip is possible over the holiday weekend (Thu-Sun). The first is Thu evening/night, when a shortwave trough and associated vort max will progress through the region. Most EPS members produce precip over the region during this period, although amounts are fairly light (0.1 inch or less) and have trended lower in recent runs. Thermal profiles during this period suggest that an all-rain event is likely. This update will feature likely PoPs along the I-94 corridor, with chance PoPs elsewhere. Another precip episode is possible on Sat night into Sun in conjunction with the aforementioned mid/upper-level cutoff low lifting northeastward toward the region. Forecast confidence regarding this period is still limited, given the considerations noted earlier, and precip amounts will likely be sensitive to the placement of the midlevel low and its associated surface features. However, EPS and GEFS means have shown a trend toward warmer surface temps during this period, and EPS/GEFS probabilities of subfreezing temps on Sat night have lowered, suggesting a limited risk of freezing precip. An all-rain scenario or perhaps a rain/snow mix in some areas appear most favored during this timeframe. Chance PoPs will be maintained with this update-- highest south.