Tech Disco 3-12

Synopsis

Today we saw how a ridge aloft combined with warm advection can warm the state well above average in terms of temperature, and this wamth will remain persistent throughout the week as well as next week as higher heights remain within our general vicinity for a long time to come. We'll have a few perturbations to this based on showers and fronts, but there are little dynamics helping to induce surface convergence, cyclogenesis, and frontogenesis leaving us to believe this week will be rather bland for activity, but pleasant for the "early taste" of Spring.

Short Term (Tonight through Tuesday)

With a low advancing and clouds starting to settle in, as well as rain falling in the west, tonight will be dominated by rainfall throughout the eastern 75% of the state. The current rainband is covering about a third of the state, and it took about 5 hours for it to completely cross the Ohio border. This shows that this first band should be out of the state by sunrise Tuesday, leaving about .10" in the east to 0.25" in the west in its wake.  There is a second band of rain oriented along the low's cold front set to impact around 12z in Erie with light rain, based upon lifting along the front over Lake Erie, with a northwesterly wind involved as well. This will be a short lived band, dissipating quickly over the mountains throughout the morning. To note about the models: the 12z GFS has a better grip on the rain right now, just slightly better than the NAM, making the GFS more believable. The GFS backs down on the lake enhanced rain, but it has a trace, and the GFS in general cannot resolve fine rainbands such as that one, giving us a good feeling for light rain in Erie in the morning. Behind this. An area of high pressure will begin to move in , allowing for decreasing clouds throughout the evening and overnight hours Tuesday. This is also when the next ridge will move in, allowing for temperatures to return to the mid 60s to near 70s regime, well above average for the state as a whole.  

Long term (Wednesday thru Friday)

 With this high moving in, there is a strong presence of a W to WNW wind.  The high's positioning implies a wind blowing perpendicular to the ridges and valleys, and even though the models stray away from clouds Wednesday afternoon, the dynamics in this situation imply low level gravity wave clouds that form,  implying for more clouds than what the models suggest.  This should not heavily impact the temperatures for the day, maintaining decent sunlight within a ridge and keeping temperatures above average. This ridge remains in place throughout the remainder of the week. The models, however, have isolated showers along the eastern U.S. Thursday afternoon. The oresence of this in a strong rideg makes in unfeasible, especially without PVA for it's accompanying low, but there is warm advection throughout the entire area, along with a cast area of radiation, implying that these cells are primarily the result of convection with showers forming from moisture collected from the Great Lakes. The net propagation of the system is eastward, so there is a decent chance for showers Thursday afternoon, and as the system moves further east Friday, the 12z long range GFS shows the low as merely a broad area of convergence with this convection. With this in mind, we could see convective clouds and showers Friday, atypical of late winter and more typical of mid Summer. However, this is an atypical late winter setup, so refreshed model runs will hopefully give us a better grasp on this late week scenario. Also, note the massive oblong ridge for next Tuesday, we have 500mb heights cveragin around 5800m for PA, which may induce record high temperatures for next week!