midatlanticweather

WPC getting in on potential for heavy downpours!

https://origin.wpc.ncep.noaa.gov/metwatch/metwatch_mpd_multi.php?md=0343&yr=2021

Lots of wild interactions with outflow boundaries tonight. Wild to see stuff collide and sometimes explode in convection. 

30 minutes ago, Kmlwx said:

One thing I'm not sure I like seeing so close to the metro areas - is GAI's dewpoint has dropped to 57. Even CGS is down to 59. The immediate DC stations like DCA, ADW etc are still in the 60s, though. My (potentially not the greatest) sensor here in Colesville has gone from the mid-upper 60s down to 61.7 for the dew. We'll ideally need to advect some of the higher dewpoint air back in for my liking. I don't think we are going to get it done with 50s dews. That potentially could be why some of the CAM runs have shown the activity really getting going only once east of I-95. Could be a little razor thin margin for those in places like MoCo and western half of Howard. 

I see a DP on my Weather station of 66 now.. That feels a bit high as it feels pretty nice outside. Will have to see. I feel another meso is coming soon for the MD/NoVa area. BTW - I know feelings mean nothing when it comes to weather.. just seems like that is the next area that could be impacted in some way.

35 minutes ago, Rhino16 said:

Could it also be a cold air funnel? It’s hard to see the ground, so I can’t tell what’s happening.

I have no idea.. cold air funnels, I would think, would happen in winter. Maybe it is any time that there is enough contrast in temps that it would occur.

51 minutes ago, vastateofmind said:

Honest question -- I'm assuming the winds surrounding some tornadoes could easily "grab" that plane and flip it around a good bit, no doubt stalling it and sending it hurtling back toward earth....right? I love to see a good chaser video....but hate to see people make dumb decisions to get closer to the phenomenon (kinda like this dude).

Yea, this looks like a landspout and not a major tornado by the way he is flying. Like small waterspouts, they can have lighter winds. 

From Landspout - Wikipedia

Landspouts are a type of tornado that forms during the growth stage of a cumulus congestus cloud by stretching boundary layer vorticity upward and into the cumulus congestus's updraft. These generally are smaller and weaker than supercell tornadoes and do not form from a mesocyclone or pre-existing rotation in the cloud. Because of this, landspouts are rarely detected by Doppler weather radar.^[3]

Landspouts share a strong resemblance and development process to that of waterspouts, usually taking the form of a translucent and highly laminar helical tube. "They are typically narrow, rope-like condensation funnels that form while the thunderstorm cloud is still growing and there is no rotating updraft", according to the National Weather Service.^[4] Landspouts are considered tornadoes since a rapidly rotating column of air is in contact with both the surface and a cumuliform cloud. Not all landspouts are visible, and many are first sighted as debris swirling at the surface before eventually filling in with condensation and dust.

WOW! 

9 minutes ago, Eskimo Joe said:

Watching coming shortly to our NW.

Yep.. It is posted

https://www.spc.noaa.gov/products/watch/ww0269.html

Incoming 

5 minutes ago, George BM said:

Oh wow. I'm actually a little surprised that the line hasn't fallen apart yet as they cross over the Blue Ridge. I saw the meso as well. Well see what transpires over the next few hours... not that I'm expecting hurricane-force winds. 

Latest 2 frames looks like it is weakening some now. 

That cluster in Pennsylvania is interesting. We will see how all this pans out today, but it has my interest. 

0.8 today. 1.38 last 24 hours.

Culpeper is also looking really bad. Wow. 7inches plus showing up on Radar and the storms keep raining. 

That was quite a bit of rain for about 20 minutes.. then lighter for about 10 more.. quick half inch picked up IMBY.

2 hours ago, MN Transplant said:

We leave ours on all of the time for a couple of reasons:  1) air filtration and 2) tapping into the natural cooling of our walk-out basement.  It is a 2014 install and I’ve been very happy with the energy usage.

Yes.. that is good. During super humid times though, this may drive up the humidity in the basement if it is evaporating the condensation off the coils. Probably not as big of a deal up here as it is in Florida from what I have read/seen on videos. You need the dehumidification the coils bring down there. Also, not a great thing to do in the Desert areas where attic vents would blow hot air into the home .. in desert areas the units are, many times, in the attics.. but I have been experimenting with leaving them on as well since the basement is a natural cooler as well.

17 hours ago, mappy said:

 

Moved this to banter as to not clog obs. It is my understanding that we do have a fan that often runs when the AC is not putting out cold air. I could be wrong however lol 

but yes at the moment we can’t turn the ac off, at least I don’t think do. Not that we would right now. I could be confused. I know we can’t turn on the heat, that I remember the hvac guy saying. 

You my be right! Some newer units have multi speed fans and run all the time. The slower speeds when not actually doing the cooling! There is a big debate out there on whether to run them all the time or only when the AC or Heat is running. I think it is all about where you live in the country and how humid it is. Good luck!! Hope it goes better the rest of the year! 

6 minutes ago, KAOS said:

Are you saying that the furnace (indoor) fan runs even when the AC (outdoor) is not "pumping out cold air"? And why if you turned it off would you not be able to turn it back on? Forgive me if this was already discussed. Assuming the fan is running while the AC is not pumping out cold air, that alone will cause high levels of humidity. The fan needs to cycle with the AC. This gives time for the condensation to run down the indoor coil and drain out of the condensate line. Otherwise you are just re-circulating most the humidity in your house.

Ya! Running the fan continuously will put humidity back in the home as it evaporates it off the coils while still inside. This is especially true with all the humidity! @mappy

AC troubles stink! Sorry you are stuck with that challenge and expense. 

3 hours ago, WeatherShak said:

Wasn’t even aware of the eclipse. Thanks for sharing.

Our issue may be the clouds. As of now showing a 60 - 65% coverage on the forecast. Hoping this is not correct, and it may not be.. but it is so humid out there that you may cause cloud cover by opening the door and letting a small bit of AC air out! 

Anyone got some ideas on cloud cover/fog around sunrise tomorrow? Just thinking of the eclipse. 

Convection firing up in central Loudoun. Just to my east. Look like heavy rain - slow movers.

Shows tornado forming on ground. Little guy.. But cool

There ya go!

16 minutes ago, SnowenOutThere said:

Tell us what its like! Any hail?

Lot of rain, thunder, and lightning.. no hail. 

It is here 

Looked a little bow-like on radar just west of Loudoun

All Western Loudoun now in a Severe Warning now. 

EDIT: The bow-like look collapsed after this frame..