LOCAL WEATHER -- WEDNESDAY, JULY 30, 2014

Discussion:

The upper air pattern across the country has a ridge across the western U.S. where very hot temperatures have been recorded -- up to 111 degrees in eastern Washington State -- while a trough carved out from a deep upper low north of the Great Lakes exists across the eastern half of the country. This puts Texas in northwest flow aloft. At the surface, high pressure is located over the Gulf with a frontal boundary, nearly stationary yesterday northeast of the area, is now pushing back to the north as a warm front over north Texas. Morning soundings and satellite-derived data indicate drier air has moved into the area, although near-surface moisture remains. Precipitation is not expected today, but hot temperatures are expected with highs in the upper 90s to lower 100s. A few clouds are expected in the early part of the overnight period with a stratus deck expected to form across many locations soon afterwards. This will burn off early Thursday. A shortwave disturbance riding around the ridge and down the west side of the trough will move toward northeastern Texas late Thursday. This feature will help push the frontal boundary back to the south. Convection is expected to develop along the frontal boundary and push into the area beginning Thursday night. The boundary will move across the area through Friday evening with convection continuing along it. Relatively high precipitable water values will allow for pockets of locally heavy rainfall, but forecast 850mb flow (around 5000 feet MSL) is not expected to be strong, so this should negate more widespread heavier rains. The frontal boundary will gradually lose its identity over the weekend but will be close enough to the area so that slight chances for rain will continue through the upcoming weekend, especially since we will still be under northwest flow aloft and there will be the risk for one or two disturbances to move across the area which could briefly cool the mid levels of the atmosphere and provide some lift enhancement. Models indicate that upper level high pressure tries to rebuild across the area next week but a general weakness in the ridge is shown to remain across the area, which would mean at least slight chances for daily convection, likely associated with the seabreeze.

For the period August 4-8, CPC is forecasting near normal temperatures and a 33% probability of below normal precipitation.
For the period August 6-12, CPC is forecasting a 33% probability of above normal temperatures and near normal to a 33% probability of below normal precipitation.

Seeding operations:

Seeding operations are not expected today. There is a chance for seeding operations Thursday and Friday.
So far in 2014 there have been 17 days of seeding operations: three in May, seven in June and seven in July.

Aviation:

Any remaining MVFR ceilings across a few central and northern locations should become VFR very soon. VFR conditions are expected today and tonight with FEW Cu possible at/above 5000 feet. Overnight MVFR deck forms around 1200-1500 feet and will burn off Thursday morning.

Forecast:

Today: Sunny with a few clouds. Highs in the upper 90s to around 103. S & SE winds 10-15 mph.

Tonight: A few clouds, then increasing cloudiness overnight. Lows in the mid 70s. S & SE winds 10-20 mph decreasing to 5-10 mph overnight.

Thursday: Early morning low cloudiness then sunny with a few clouds. Highs in the upper 90s to around 103. S & SE winds 10-15 mph.

Thursday night: Partly cloudy. Chance of showers and thunderstorms, mainly northern half of target area. Lows in the mid to upper 70s. E & SE winds 5-10 mph.

Friday: Partly cloudy. Chance of showers and thunderstorms. Highs in the low to mid 90s. E & NE winds 5-10 mph.