Well, keep dreaming.
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Issued at 215 AM EST Mon Dec 21 2020 The GFS and NAM show strong ridging building aloft over the plains states in the wake of the departing short wave. This sets up and excellent pattern for lee side subsidence across the Mississippi and Ohio Valleys. Strong surface high pressure is depicted to build across the plains tonight and push across Indiana through Wednesday morning. Forecast soundings and Time height show a very dry column as this system passes. Thus will trend toward partly cloudy skies through Wednesday Morning. Given the expected arrival of southerly flow on Tuesday and Tuesday Night...will trend temps at or above NBM. On Wednesday a strong cold front will approach Indiana. Aloft...a deep upper low will push through the upper midwest and into the Great Lakes. This nearly stacked system will drag the cold front across Central indiana in the afternoon...with favorable forcing dynamics and strong cold air advection in its wake. Forecast soundings show deep saturation on Wednesday afternoon and evening as the cold front passes...with the soundings being above freezing. Thus Ptype on Wednesday and Wednesday Night will be rain ahead of the front with plentiful warm air in place due to southerly flow on Tuesday and Tuesday Night. Forecast soundings dry out considerable in the wake of the front as the cold air arrives overnight. Thus will trend toward a dry forecast at that time. && .LONG TERM /Thursday through Monday/... Issued at 346 AM EST Mon Dec 21 2020 Following frontal passage on Wednesday night, unimpeded NW flow will push an Arctic airmass into the Midwest and Ohio Valley. Even with diurnal heating, efficient CAA will steadily drop temperatures throughout the day with morning highs in the low 30s and afternoon highs in the mid 20s. High temperatures in the mid 20s would be within the 10th percentile climatologically, but this is supported by thickness values less than 5200. With surface high pressure building underneath the CAA, dry weather is likely to continue for the end of the week. With the vorticity max centered over the Ohio Valley, some lingering cloud cover is likely, although this should scatter by Friday morning. With lows expected in the low teens and winds greater than 10 knots Friday morning, wind chill values are expected to be in the single digits. Another amplified trough will approach from the west over the weekend, pushing temperatures back towards seasonal. A surface disturbance looks possible towards the end of the period, but a large distribution in location across ensemble members has lead to lower confidence. Even so, some form of precipitation is possible
late on Day 6 and Day 7.
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