10/14 – Brittany’s “Cool & Quiet” Friday Night Forecast
A departing surface high and an increased onshore flow regime will be the primary drivers of the weather forecast through Saturday night. As southeasterly flow increases tonight into tomorrow, dewpoints will correspondingly increase in the low levels.However, continued ridging in the mid and upper levels will remain in place through tomorrow before the ridge begins pushing east of the region by tomorrow night. As a result, a very dry and very stable airmass will remain in place aloft, and this will greatly inhibit any cloud development and rain chances through the short term period. The largely clear skies both tonight and tomorrow will allow for strong radiational cooling. At the same time, higher dewpoints will be advecting into the area. The resultis high relative humidity both tonight and tomorrow night within the boundary layer.
The main story in the extended range forecast will be a very strong northern stream trough digging into the eastern half of the CONUS. In advance of this trough, a brief window of deep layer onshore flow will occur Sunday into Sunday night. A surge of moisture will feed into the mid-levels, and precipitable water values are expected to rise between 1.5 and 1.75 inches by Sunday night and remain at those levels into Monday. Additionally, increasing positive vorticity advection and a broad region of upper level ascent will overspread the Gulf South. The result of this increased moisture and lift over the region will be mostly cloudy skies and scattered showers on Monday.