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The weather was pleasant and tranquil last week. Temps some mornings were in the 30's, the Fall Foliage began to peak, and we did not see any measurable rain. The week went as expected. Quiet.
WEEK OF 10/17 - 10/23 FORECAST:
I am giving the greenlight for summer-like weather to return this week. I know it's Fall, but I kind of miss the summer and look forward to feeling the warmth. It will not last. A strong frontal system will come through later this week. The possibility exists a strong low pressure system develops off our coast. I'll discuss more. Keep reading!
Monday - Wednesday: Expect abundant sunshine with high temperatures reaching the low to mid 80's. Figure 1 is the GFS 500mb height anomaly which depicts a strong High Pressure system to our south and east allowing winds to flow from the southwest. The southerly flow will pump Gulf air into our region and keep us well above normal for a few days. No rain is expected during this time.
Figure 1 - Southeast ridge turns winds out of the southwest and keeps our area under much an above normal temperature regime
Thursday: I think Thursday morning will start off sunny, but clouds and even some light showers could develop by the afternoon. I am leaning against rain for Thursday at the moment but be wary there could be some showers in the afternoon. High temps will still be mild - likely in the mid to upper 70s.
Friday - Saturday: The potential is there for a strong coastal storm to develop. I am not feeling as confident about this threat as I was over the weekend, but it's still worth talking about. Figure 2 is the 500mb heights pattern from the EURO. The deep shades of blue in the southwest Atlantic an area of low heights that contains upper level vorticity, or energy. If this area of "energy" organizes itself better, it could be classified as a weak tropical disturbance. The EURO shows a sweeping trough coming across the Great Lakes which tries to capture the Atlantic energy and turn it into a strong coastal low off our coast.
Figure 2 - EURO tries to phase Atlantic energy with a frontal boundary elongated along a trough
There are 3 reasons why I feel this set-up may not evolve in time for our area to be effected by a Nor'easter:
1. The separation between the Atlantic energy and the Great Lakes trough may be too distant.
2. The Pacific Northwest still shows a zonal look (fast flow from northern jet) despite the western ridge centered over Arizona.
3. The energy embedded within the Atlantic trough may fizzle out or escape east.
Figure 3 does a good job of showing the first 2 concerns.
Figure 3 - The pieces for a strong coastal storm are there, but the timing between them looks off and the upper pattern does not look conducive
That said, we may not need the Atlantic energy to get a strong storm to pop near our area. The GFS, as shown in Figure 4, shows the trough digging into the southeast and closing off. The H5 upper level low occludes and begins tracking east-northeast, cut-off from the jet stream.
Figure 4 - Very strong upper energy associated with a digging trough cuts off from the main flow
If this upper low phases with a separate piece of northern energy that may try to come down from Canada, a coastal storm will form and likely track up the coast. Models are not really showing this at the moment, and it could be because the upper level pattern just does not look ready with a +NAO/-PNA. At this time, I would expect either Friday or Saturday to be cloudy with light to moderate rain. BOTH days have the potential to be crappy if the pattern comes together for a coastal storm to come up the coast. But most likely it will just be one of these days.
Sunday: Temps return back to normal in the 60's. It should be dry and sunny too. At least we have 1 day next weekend we know looks good unless the timing of the possible coastal storm delays itself.
Once we get through the weekend ordeal, temperatures are expected to return to normal. Models are very consistent in showing a -NAO developing and a trough settling in over the northeast. It remains to be seen whether this is a short-lived trough or one that sticks around for a bit. Given the state of the Pacific, I am willing to bet it will be short-lived. But we should still see below normal temps Monday - Tuesday the week of the 23rd.
It is WAY too soon to begin speculating what Halloween could be like, but I'll give my educated guess and update everyone in next week's blog. At this time, I think Halloween will be sunny with temps in the 60's. Could be windy too. More to come next week :)
Thanks for reading.
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