Mountain Area Forecast ( June 3-5 )

A significant increase in moisture is expected by late Sunday into Monday, with showers and downpours in thunderstorms.  Locally heavy rainfall amounts will be possible before much drier air returns by June 6.

Overnight Into Saturday Morning

Clear.  Seasonally chilly.  Large vertical temperature spread between colder mountain valleys and milder ridges.  Light winds.  Temperatures varying from 39 to 43 degrees in the coldest mountain valleys to the mid-upper 50s along milder mountain ridges.  Areas of dense river valley fog.

Saturday Afternoon

Sunny.  Beautiful blue skies.  Light northerly winds.  Temps varying from low-mid 70s in upper elevations to the lower to mid 80s.

Saturday Night Into Sunday Morning

Clear.  Large vertical temperature spread developing between colder mountain valleys & milder ridges and plateaus.  Light southerly winds along mid-upper elevation mountain ridges.  Temperatures varying from 40s in the colder mountain valleys to the low-mid 60s on exposed mountain ridges.  Areas of dense river valley fog.

Sunday Afternoon

Increasing clouds.  More humid.  A chance of showers and thunderstorms.  Local downpours.  SW winds 5 to 10 mph.  Temps varying from low-mid 70s in upper elevations to the low-mid 80s.

Sunday Night Into Monday

Warm & humid. Showers & downpours in thunderstorms.  Locally heavy rain amounts.  SW-W winds 5-15 mph, with higher gusts, on mid-upper elevation mountain ridges.  Areas of fog, especially at upper elevations.

A period with showers and downpours in thunderstorms will be followed by another spell of below average temperatures ( chilly nights in mountain valleys ) next week ( as Florida turns wet ).

Weather Discussion ( Cool Nights )

A chilly night is underway in the mountains, with light winds and clear skies generating large vertical temperature spreads between colder valleys and exposed ridges.

Gorgeous blue skies observed Saturday afternoon indicated that low dewpoint air had advected into the mountain area.  This sets the stage for coldest valleys to drop into the upper 30s to low 40s in contrast with 50s along exposed ridges and plateaus.

A very low precipitable water atmosphere ( above ) will be in place through Saturday into Sunday morning to allow for large diurnal temperature changes between night and day.  Note the tropical moisture across the Gulf of Mexico and Florida.

A large diurnal ( day-to-night ) temperature spread will also be observed into Sunday, with rapid warming by day giving way to another significant temperature drop in mountain valleys during Saturday night into Sunday morning.

A significant increase in moisture is expected by late Sunday into Monday, with development of showers and downpours in thunderstorms ahead of a upper air trough and surface cold front.  Much drier air is expected to then return by Tuesday ( below ).

This will mark the beginning of an unseasonably cool period, with more chilly nights in the mountains.

As I alluded to before, rising air in association with a plume of tropical moisture and deep convection across Florida and the Gulf Coast will contribute to this next cool period ( some may call it Elderberry Winter ) via synoptic-scale sinking of air ( subsidence ) over the southern-central Appalachians.