Powerful low pressure system to continue producing gusty winds andheavy rain across parts of the Great Lakes, Ohio Valley, Northeast, andAppalachians through tonightLower elevation rain and mountain snow to enter California onSaturday.Well above average temperatures forecast to surge into thenorthern/central Plains this weekend.A deep low pressure system churning over southeast Ontario, Canada thisafternoon is responsible for widespread shower activity extending from theGreat Lakes and upper Ohio Valley to New England. Additional heavy rain ispossible through tonight across New England and parts of Upstate New York.Isolated instances of flash flooding are possible, especially where recentsnowmelt has led to elevated river levels and saturated soil. FloodWatches and Warnings are in effect for parts of northern New Hampshire andwestern/central Maine. Additionally, a few thunderstorms are possible andcould turn severe over eastern New York and western New England. A tightpressure gradient is also producing gusty winds surrounding the stormsystem. Wind Advisories are in effect for parts of the Great Lakes, OhioValley, and Appalachians due to the potential for wind gusts up to 50 mph.As the system exits deeper into Canada on Saturday, rain could change tosnow over parts of northern Pennsylvania and New York, with windsgradually waning.For the West Coast, an approaching storm system is expected to spreadlower elevation rain and high elevation snow to California beginningtonight. Rain could be heavy enough at times along the central andsouthern coastal ranges to produce isolated flooding concerns. The SierraNevada and northern California mountain ranges could see upwards of 6 to12 inches of snowfall. Meanwhile, gusty winds are forecast to develop overthe high desert regions of eastern California and Nevada on Saturday,where High Wind Warnings, Watches, and Wind Advisories are in effect. Asthe system weakens and pushes inland across the Intermountain West onSunday, showers and thunderstorms are possible across the northern GreatBasin.Outside of areas experiencing rain showers (West Coast and Northeast)early this weekend, well above average temperatures are forecast todominate the second weekend of April. High temperatures 20 to 30 degreesabove average are anticipated across much of the Plains and Upper Midwest,with the highest anomalies centered over the north-central United States.This equates to widespread afternoon highs into the upper 70s and 80s. Low90s could also be felt throughout parts of the central and southern Plainsby Sunday.