Jump to content

Mailman

Members
  • Posts

    1,482
  • Joined

  • Last visited

Everything posted by Mailman

  1. Mesoscale Discussion 0080 NWS Storm Prediction Center Norman OK 0324 PM CST Sun Jan 16 2022 Areas affected...central Appalachians and upper Ohio River Valley Concerning...Heavy snow Valid 162124Z - 170330Z SUMMARY...Mixed wintry precipitation has begun to transition to moderate snow across portions of eastern KY, southern OH and WV. An increase in heavy snow is expected late this afternoon and evening with rates of 1 to 2 inches per hour possible. DISCUSSION...Moderate and heavy snow should continue to become more common this afternoon and evening across portions of the central Appalachians and Ohio Valley ahead of a potent upper low moving out of the southeast. Strong diffluence aloft overspreading the ongoing precipitation has resulted in increasing coverage and intensity with several reports of moderate snow appearing in eastern KY over the last hour. As large-scale ascent and strong mid-level warm advection continue to increase through this afternoon, precipitation rates should follow suit, increasing after 22z. It still may take several hours for the entirety of the precip to change over to snow given warm air trapped on the windward side of the Appalachians. However, dynamic cooling from increased precipitation rates and the loss of diurnal heating should accelerate the change over after dark. Hi-res guidance is in strong agreement that band of moderate to heavy snow will likely take shape within the axis of deformation across eastern KY, western WV and eastern OH over the next couple of hours. This band will likely support snow rates of 1+ inches per hour through late afternoon and into this evening as it migrates north eventually reaching eastern OH and western PA. The corridor along the OH/PA border appears most likely to see the heaviest snowfall rates given the favorable overlap with strong isentropic ascent at the nose of the warm conveyor and enhanced deformation to the northwest of the upper low. Snow rates may briefly approach 2+ inches per hour within this corridor, especially on the windward side of any locally higher terrain. ..Lyons.. 01/16/2022
  2. .NEAR TERM /THROUGH MONDAY/... Changes for the late aftn update included the insertion of a freezing rain mention for areas east of I 79 given some initial reports south of I 70 as well as a model trend of strong warm advection support for that scenario. Overnight totals for those areas will likely be degraded a bit given the retardation of dendritic growth. Nevertheless, deformation on Monday will support continued and prolonged snowfall, so snow totals remain the dominant feature of this event. Elsewhere, the expected frontogenetic band with 1-2 inch/hour rates is also likely to be shunted slightly westward and a storm total tweak was completed for that eventuality. Gusty wind is expected to develop in the eastern WV ridges on Monday, and will likely result in blowing snow and lowered visibility.
  3. Well.. at least the NAM lost the historic freezing rain scenario. Now it's a historic dry slot. lol.
×
×
  • Create New...