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This is from the weather app WX weather

 Probabilistic Heavy Snow and Icing Discussion NWS Weather Prediction Center College Park MD 416 PM EDT Sun Apr 30 2023
Valid 00Z Mon May 01 2023 - 00Z Thu May 04 2023
...Upper Great Lakes... Days 1-2...
A cold core and expansive upper low will move very slowly eastward from MI to Upstate NY through midweek in response to the exceptionally amplified pattern across North America, and work in tandem with coupled jet streaks to drive pronounced synoptic ascent across the Great Lakes. The result of this synoptic lift will be a deepening area of surface low pressure which will likely retrograde north of lakes MI/Huron Monday before tracking over southern Ontario Tuesday, leaving a cold airmass across Lake Superior and areas south. As this low deepens, moisture advection will increase as 285-290K isentropic ascent surges a theta-e ridge cyclonically into the Great Lakes, and where this overlaps with a cooling column on intensifying northerly flow /CAA/, heavy snow will be the result. Although 850mb - lake sfc temperature differences are expected to be generally less than 10C, the persistent fetch across Lake Superior will drive lake enhanced precipitation. Where this flow then intersects some of the higher terrain of the U.P., including the Gogebic, Porcupine, and Huron ranges, a long duration of heavy and rather wey/very dense snow with rates greater than 1"/hr in spite of SLRs generally 7:1 to 10:1 will occur.
The overall column remains marginally cold for all snow, but in higher elevations and/or during periods of more intense ascent sufficient dynamic cooling is expected to produce heavy snow. So near lake level, expect a mix of rain and snow at times. This leads to a challenging accumulation forecast, and a situation where effective SLR due to melting/daytime sun angle could be much lower than the SLR otherwise supported by the atmosphere. Expect then that this snow will be very heavy and wet, but still be able to accumulate rapidly and efficiently at times, as already seen last night with 6-8" reported over much of the Interior western U.P. into northern WI. 12Z guidance continues the trend of increased snowfall, especially in the western and increasingly central U.P. through Monday night. It is likely that many areas a few hundred feet above lake level will receive 1-2 feet of snow, and despite the low SLR and high sun angle, see continued increase in snow depth through the event. There is an isolated risk for 4 feet of snow, particularly in the highest portions of the Huron Mtns in central U.P. where 12Z guidance focuses the prolific precipitation with this event. With this being a heavy and wet snow, expect extreme impacts as noted by the WSSI/PWSSI, with tree damage and power outages expected.
 ...Central Appalachians... Days 2-3...
A cold core low will drift east from Michigan to Upstate New York through Tuesday, resulting in sharp cyclonic flow across the Central Appalachians. Lobes of vorticity swinging through the flow will drive periodic enhanced ascent, aided by steep lapse rates and left exit diffluence as a jet streak develops across the Southeast. The column will be generally quite cold for early May, with 850mb temps falling below 0C, but still generally marginal for wintry precipitation below about 2500ft. The westerly upslope flow into the terrain of east-central West Virginia should produce periods of moderate to heavy snowfall Monday into Wednesday. WPC probabilities for >6" are 30 to 40 percent for areas above about 3000ft on Day 2 with probabilities 10 to 30 percent for an additional >6" for Day 3. There is a risk for 24" storm total snow above 4000ft which occupies little territory in WV. Some light snow accumulations are likely above areas over 2500ft with moderate probabilities for >2" extending up Garrett Co MD and into the Laurels in SW PA. For higher elevations, impacts will worsened by low SLR on trees that have already leafed-out.
 ...California... Days 2-3...
Strong low off the WA coast this afternoon will eject south as a reinforcing shortwave trough plunges from the Gulf of Alaska on account of the omega blocking ridge centered over the Intermountain West. This low will continue to deepen as it digs southward to the north-central CA coast, directing increasingly moist onshore flow through downstream confluent flow beneath a modest jet streak rotating around the base of the trough into CA, especially after 00Z Tuesday. A surface low tracking southward in tandem will help enhance ascent, resulting in an expanding shield of precipitation spreading across CA, which will be snow in the higher elevations. Snow levels will be generally 5000-6000 ft over the Sierra Nevada Monday night into Wednesday, with steep lapse rates beneath the upper low potentially allowing precipitation to drag down snow levels toward 4500ft Tuesday. Locally heavy snow can be expected above these elevations, primarily in the Sierra Nevada where upslope flow will additionally enhance ascent. WPC probabilities for >6" are moderately for the central and northern Sierra Nevada for both Days 2 and 3. Storm total snowfall in the central High Sierra exceeding 12 inches is likely, and impactful snow is likely at the Sierra Passes, including I-80 between Blue Canyon and Truckee.
 The probability of significant icing greater than 0.25" is less than 10 percent.

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