Scientific Forecaster Discussion
fxus62 krah 181039
Area forecast discussion
National Weather Service Raleigh NC
630 am EDT Wed Sep 18 2019
a Canadian high pressure will build down the eastern Seaboard
today through Friday, bringing much cooler and less humid
conditions. High pressure will become stationary over NC this
weekend, keeping dry weather in place, with a gradual warming trend.
Near term /tonight/...
as of 125 am Wednesday...
The cloudiness associated with the backdoor cold front will
gradually shift south and west of central NC through the morning
hours. Some stratocumulus may linger in the western Piedmont into
the early afternoon, then skies are expected become mostly sunny
this afternoon. Sunny skies are expected NE and east. Highs generally
in the mid to upper 70s north, ranging into the lower 80s south.
The wind is expected to die off this evening in the Piedmont under
the building ridge. The boundary layer may stay mixed a bit longer
in the coastal plain given the tighter pressure gradient on the
periphery of the ridge. The very dry air mass in place will lead to
excellent radiational cooling in the Piedmont. As the wind dies off
in the east, temperatures will fall quickly after midnight. Lows
generally in the lower to mid 50s, except some upper 40s north-
Short term /Thursday and Thursday/...
as of 125 am Wednesday...
The high pressure will be overhead Thursday and Thursday night.
Expect sunny skies Thursday with highs in the 70s. Clear skies and
exceptional radiational cooling are expected Thursday night. Lows 45-
50 north and 50-55 elsewhere. We did trend the mint forecasts toward
the cooler guidance given the expected exceptional radiational
cooling, especially in the rural and typically cooler areas.
Long term /Friday through Tuesday/...
as of 225 am Wednesday...
High pressure is forecast to park over central NC Friday and
Saturday. The high pressure is forecast to shift just east of the
region on Sunday afternoon and night, allowing a more south-
southwest return flow. Expect dry conditions with slowly moderating
temperatures Fri-sun. Lows Friday in the mid 40s to mid 50s, warming
into the mid to upper 50s by Sunday. Highs 77-82 Friday, warming
into the mid to upper 80s Sunday.
The strong, blocking, persistent mid/upper ridge is expected to
slowly shift south from the Tennessee Valley toward the Gulf Coast states
Monday and Tuesday. This will allow another front to approach by
late Monday and Tuesday. It appears at this point that the Gulf and
Atlantic will remain closed for our region - blocked by the
persistent ridging. Therefore, the chance of any showers appears
very low even with the passage of the next front. Temperatures early
in the week should warm to above normal and remain there next week.
Aviation /12z Wednesday through Sunday/...
as of 630 am Wednesday...
VFR ceilings in the kgso/kint/krdu areas will give way to mostly
sunny skies later this morning or early this afternoon. VFR
conditions are expected with high confidence this afternoon and
Looking beyond 12z Thu, VFR conditions will dominate through the
weekend under high pressure. High confidence.