1.) Coast-to-coast cold: The Lower 48 is waking up in an ice box this morning as widespread arctic air and below normal temperatures engulf the country (minus the FL peninsula this morning). The arctic express will remain with us through the weekend, including temperatures once again tonight that threaten to dip into the sub-zero range across central Indiana. Highs today will only reach the middle 10s and upper 10s to lower 20s Sunday. Bundle up and stay warm.
2.) Expanding Snowpack: 65.4% of the country is covered in snow this morning. The cold, arctic high suppressed the winter storm threat south as we alluded to in previous posts. Places across the Deep South that aren’t used to wintry precipitation are waking up to snowy and icy conditions this morning, including MS, AL, GA, SC, and into the Mid Atlantic. Heavier snowfall accumulated across east TN, including 5″-8″ in the high country. Heavy snow also fell through western and central NC and Blizzard Warnings are up in rare areas including VA Beach this morning.
3.) Moderating Temperatures: Our air flow will back around to the southwest and this will help temperatures begin to moderate early next week (around freezing Monday and all the way to around 50 Tuesday). As the moderating trend gets underway, we may have to deal with a brief period of freezing drizzle/ freezing rain Monday evening.
4.) Rainy Midweek: A more significant surge of moisture will arrive midweek and result in periods of moderate to heavy rain Wednesday PM into Thursday. Potential is present for 1″+ during this timeframe.
5.) Weekend Wintry “Fun And Games?” A tremendous battle will take place next weekend between a strong and sprawling arctic high pressure system and the southeast ridge. In between it’ll be fascinating to watch things unfold, and as you’d imagine, that includes Indiana. Despite the southeast ridge flexing it’s muscle, the concern here is that the shallow dense arctic air will “ooze” south and present an icy set-up for portions of the Ohio Valley and Mid West for the weekend. We still have some time to watch this, but the potential of significant icing is very much present for some and this will require a close eye through the week.
We note ensemble data is suggesting high latitude blocking tries to develop towards Day 10. Recall this was the missing ingredient in the bitterly cold blasts of air that occurred during the first few weeks of December. Both the GEFS and EPS agree on the increasingly blocky look to the pattern by Day 10. This would help drive a cold, stormy pattern by early January. Instead of storms cutting, we would see more suppression. With a “stubborn” southeast ridge, things could get interesting across the Ohio Valley from a wintry perspective….
We don’t want to jump the gun, but it the positives can “hook up” over the pole, we stand the chance of locking into a rather lengthy cold, snowy regime as we rumble deeper into the heart of winter.
Summary: A rather mild regime remains as we rumble through Christmas before trending more seasonable next week. From a wintry perspective we need to continue to keep an eye on the period around New Year’s Eve/ Day. Confidence continues to increase on the potential of a return of arctic air come early January.
We’ll open the work week with dry and cold conditions, but all eyes will be on the next arctic front by this time. It’ll blast through here the middle of the week with