The National Weather Service predicts a warm southwest flow into the region through Wednesday to Thursday due to surface high pressure building over the Southeast states, which will shift offshore. A cold front from the west is expected to approach and move through the area on Friday.
The National Weather Service in Raleigh, North Carolina, released a forecast discussion on 14th February 2023. It stated that surface high pressure will build over the Southeast states, resulting in a warm southwesterly flow into the region from Wednesday through Thursday. A cold front is expected to approach the region from the west on Thursday night, and it will move through the area on Friday.
As per the report, the latest surface analysis shows that an inconsequential weak trough is dropping SE through North Carolina. High pressure centered over the NE Gulf covers the Southeast states, and its ridge extends northward to the Ohio Valley. This surface ridge will shift eastward over the area today, topped by a corresponding mid-level ridge axis.
Incoming mid and high clouds will thicken this evening through tonight as the S Plains shortwave trough lifts NE through the central Plains and Midwest to near Lake Superior, dampening in the process as the mid-level ridge axis holds over the E Carolinas. With the surface ridge shifting to our E and offshore, weak return flow overnight will help boost low-level moisture such that some patchy fog/stratus are possible late tonight over eastern sections.
The highs for today will be in the mid-60s to lower 70s, as projected by the report. The report also predicted that low-level thicknesses are expected to start the day around 30 m above normal, supporting highs at least a category above the deterministic NBM and closer to the warm end of statistical guidance.
The report further stated that mid/upper-level ridging will be in the process of shifting offshore on Wednesday morning as a shortwave races up into the Great Lakes Region. This eastward suppression will open southwesterly flow aloft and begin to increase deep layer moisture over the southern Mid-Atlantic.
As per the report, the cold front is likely to produce a longwave positively-tilted trough Friday morning, which is expected to push east and off the coast by Saturday morning. The report mentioned that there still remains some timing differences with this trough, which is likely tied to how each respective model handles this phasing of the two disturbances.