osfan24

Had some decent thunder and lightning but tonight doesn't seem like anything more than a quick line of storms. Not seeing a flooding threat until the weekend.

HRRR and NAM certainly are not very interesting for today or tomorrow. Looks like Saturday or more likely Sunday is when we get pretty much all the rain.

46 minutes ago, losetoa6 said:

Gfs really closes off at 500 over us Saturday and look at 700 mb moisture core ..it's right over us .Interesting like others have said. Someone could get crushed .

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What do I have to do to get this in January?

1 hour ago, Eskimo Joe said:

Slowly getting interested in the flooding and conditional severe potential for the Thursday - Saturday timeframe.  SE flow + lift + remnant tropical system = intriguing.

Yeah the NAM and GFS are both hinting at that, especially Saturday, though obviously out of NAMs range.

20 minutes ago, North Balti Zen said:

I don't want to engage, really, but maybe slow one's roll with dismissing too quickly the effect that development in terms of sub-divisions and shopping centers in the hills above Ellicott City has had on what has happened in Ellicot City with the last few floods. There has been enough forest and fields lost to that development that the amount of water that now cascades into those tributaries is markedly different than where it was even 15 years ago. The previous issues that Ellicott City has had with flooding historically were from the Patapsco filling up and backing into the low end of Main Street. What happened in 2016 and over the weekend was very very different - run-off from the higher ground filling and over-whelming the streams running through the town.  That is a development issue, and that has been a point of contention for locals there as the developments have been green-lit.

I'm sure it was somewhat of a factor or exacerbated the situation, but the bottom line is they had a very intense, long-duration event and the topography of the area literally checks all boxes in terms of what you would look for when it comes to a town and flash flooding. It is basically built in a valley surrounded on all sides by steep hills, is a narrow street lined with buildings, sits next to a major river and is also built on top of a river. It's essentially sitting in the bottom of a bucket or bowl. Fill up cups of water and dump them into a bowl from all sides and watch what happens.

The other evidence that this is almost entirely topography driven is that nearby Catonsville received even more rain than Ellicott City. While there was some flooding, it was not the catastrophic damage we saw on Main Street. Catonsville is more developed than Ellicott City, but it doesn't have buildings that sit near the Patapsco, nor is it built on top of a river.

On ‎5‎/‎27‎/‎2018 at 8:01 PM, PrinceFrederickWx said:

I added today's Ellicott City flooding to the July 30, 2016 option.

Good Lord...

Still think it's the derecho because of the region-wide impact, but if you combine the two flash flood events, consider the devastation to Ellicott City twice, the loss of life, and also consider this time impacted areas of Catonsville through the city to the east side, it has to be considered. It was certainly the most impactful with regard to the economy, but again, the number of people impacted is very small. Unless you live in that narrow stripe that was trained over, you hardly got any rain. I know it was just a deluge just several miles northwest of me and I got very little rain and some distant thunder.

Frankly, the image showing development above Main Street Ellicott City is not all that crazy to me. There isn't really that much development there to blame this on that. I'm sure it played a small part in exacerbating things, but anytime you have a narrow mill town at the bottom of a hill with a major river running both under and through it and you get insane rainfall rates for a few hours, this is what happens. Catonsville is more developed than Ellicott City, and while there were flood issues there, nothing destroyed the town because the river doesn't run near the developed areas and the town isn't located at the bottom of a steep hill.

1 minute ago, Eskimo Joe said:

Still need to wait for runoff to stop.

Oh got it. I took it as there was more rain coming. Yeah that's going to take some time.

6 minutes ago, Eskimo Joe said:

 

Definitely a rare event but how are we still in the middle of it? It's over.

Looks like Frederick is getting pounded again.

Seems like the northern folks managed best with both the severe/t-storm part and the rain. Down here, we had some lightning and thunder off and on for an hour or two but nothing crazy. Also had heavy rain for a period, but again, it was a couple hours and not consistently heavy.

What's the setup looking the remainder of the week? What a mess the infield will be at Preakness!

2 minutes ago, yoda said:

Radarscope must be having issues with the hail markers...  the Loudoun cell has a marker of 3.25" lol

It's had problems with both tornado signatures and indicating hail where there isn't even anything on radar today.

Looks like most of the line is losing strength. Lightning fading as well as hail. That said, Frederick is getting a crazy storm. Good thing it's not over Ellicott City!

I wonder if this line doesn't start to weaken soon and eventually becomes the focus of the heavy rain rather than severe weather.

Line to north is definitely strengthening and extending/redeveloping farther to the west. A large part of Baltimore metro should get hit.

It looks like the line to the north is starting to extend west, and the stuff to the south is starting to move a bit closer and blossom a bit.

Is the excessive rainfall prediction for today now out the window?

Got realllyyyy dark here and had some wind and then it suddenly got brighter and had a few minutes of rain. Weird. No lightning and just a few low rumbles of thunder.

It's gotten pitch black here. Very eerie.

Derecho or Ellicott City flooding, with the February 15 cold for honorable mention. All the tropical storms/Sandy were duds at my house. There was some wind, but it wasn't anything I don't see from strong fall/winter cold fronts and the rain wasn't prolific. Isabel and Floyd are the two tropical systems that register on my list. Isabel forced me to leave UMCP for a couple days because my power was out and it did some major damage along coastal areas. Floyd got me two days off of school and put down a ton of trees.