Technical Discussion
Synopsis:
A ridge of high pressure will remain above eastern 1/3 of the United States on Monday, keeping the weather calm for the majority of the Northeast. Some clouds will move into the region Monday night as a strong mid-latitude disturbance rolls across the Midwest. Some scattered showers will ensue Tuesday morning as the storm system approaches. The rain will become steady towards Tuesday evening as storm's cold front draws in a lot of moisture from the Gulf of Mexico. The rain will continue on Wednesday but gradually tapering off from east to west in the afternoon. Some lingering showers and snow showers are also possible in northwestern part of the state Wednesday night. Clouds should start to break up and give way to a fairly nice end to the week with cooler temperatures.
Short-term (Monday – Monday night)
A ridge of high pressure will continue to dominate the region, providing us minimal rising motion, and thus not very supportive of cloud developments. The skies should remain mostly sunny throughout the day on Monday. However as we progress into the evening hours, some high clouds associated with a Midwest cyclone will begin to move into the region. The clouds will gradually thicken as the night grows and expect mostly cloudy skies by Tuesday morning.
Mid-term (Tuesday – Wednesday night)
Most of the models have reached a consensus that some rain showers will develop across the Commonwealth as early as Tuesday morning. There could be a brief period of light rain and drizzle Tuesday morning as the warm air coming from the south overruns the cold air sitting over our region. However, the main bulk of the precipitation will arrive late Tuesday afternoon ahead of the approaching cold front. For western half of Pennsylvania, the rain will become heavy at times Tuesday night as the strong cold front will generate a line of heavy showers. The predicted CAPE value doesn't look too good for thunderstorm development once again this time. However with strong upper-level winds, the conditions may just be favorable enough for a chance of thunderstorms in western Pennsylvania. The chance of thunderstorms increases toward the eastern half of the state as warm air advection ahead of the cold front will also support convective showers. Most of the state will see a brief period of heavy rain as the line of showers and thunderstorms pass through the region, though still cannot rule out the probability for some isolated cells to reach the severe limit as they will likely be accompanied with localized downdrafts. Rain will continue on Wednesday, but gradually tapering off from east to west in the afternoon as the cold front sweeps through Pennsylvania. Some backend snow showers will also be possible for western half of the state as the temperatures drop quickly behind the cold front.
Long-term (Thursday – Friday)
Yeah, I know this technical discussion is pretty long already, but the week just doesn't end Wednesday night. Clouds will break up late Wednesday night and sunshine will prevail on Thursday. The temperatures will be much cooler comparing to what we will see on Tuesday ahead of the cold front. The weather conditions will remain calm for the rest of the week as another high pressure system builds back in from our west.
David Wang
No comments:
Post a Comment