Heavy Rain on Halloween Night
Good morning folks! I apologize for not posting anything yesterday. We had a family emergency and all is well, but i simply couldn't find the time to post a discussion as planned. In some way this was a good thing because the models have finally come together on how the upcoming rain event will play out across the region. Today (Monday) will pleasant with a slow increase in clouds this afternoon, more of the cumulus variety and by Tuesday we'll notice high clouds building before midday. Isolated light showers are possible Tuesday evening, first for the escarpment area and then for all of SW NC as southerly flow ramps up across the Carolinas. Wednesday will feature periods of moderate to heavy showers, with breaks of light and spotty shower activity in between, followed by the main event Thursday night. All of this is due to the upper level setup that is funneling moisture from the Gulf of Mexico into the Southeast region and as the front moves through Thursday night we expect heavy rain to unfold, followed by a distinct cutoff from rain to sunshine sometime Friday morning. Temps the entire time will be a handful of degrees above normal so it wont be too miserable but we do expect anywhere from 3 - 5" of rain across all of SW NC from Tuesday afternoon into Friday morning. A much colder weekend will follow, cold enough to break out the heavy coats during the morning hours.
We'll focus on Tuesday through Friday with this discussion, ignoring Monday since we are essentially half way through the day. Tuesday brings us the classic setup in which high clouds build during the morning hours, followed by a lowering of the cloud deck to cloudy skies as the system draws near. Temps Tuesday reach the upper 50's - low 70's depending upon elevation, so not a bad day although we do lose our sunshine. Temps overnight will not drop much as light and spotty showers develop, holding to the mid - upper 50's across most of the region.
Wednesday and Thursday will be our wettest days of the week, with a few rounds of widespread showers Wednesday, mixed in with down periods that will produce a light shower or two as the overall flow remains extremely saturated. There will be a period of heavy rain overnight into Wednesday, as the models point to one particular piece of energy rounding the upper level trough, pushing across our region around midnight. Scattered showers will continue throughout the morning hours on Thursday with periods of heavy rain as the front draws near and the heaviest round of rain should occur during the late evening hours, gradually winding down after midnight. During this 48 hour period we will pick 2 - 3" of rain and the highest amounts will be found along the N GA and SC state lines due to southerly flow throughout the entire event. Temps throughout the event will not be chilly as they warm to the upper 50's - upper 60's both days, followed by overnight lows in the mid - upper 50's Wednesday night and mid - upper 40's Thursday night.
Halloween plans should definitely be moved inside as we expect widespread, heavy rainfall during peak trick or treat hours. Another not so fortunate point to make is that the winds will pick up as the front moves through, becoming steady around 10 - 20mph as we inch closer to midnight.
Rain winds down during the morning hours on Friday, with mostly sunny skies likely overhead before midday. Temps Friday will only make it to the mid 40's along the ridgeline, while the valleys struggle to reach 60°F. Add in NW winds around 10 - 20mph and it will feel much colder, even with sunny skies overhead. Even colder temps arrive this weekend, but we'll stop here and wait till our next discussion comes out Wednesday afternoon for a more detailed look at the incoming cold weather.