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srainhoutx wrote: ↑Tue Sep 17, 2019 9:47 pm

stormlover wrote: ↑Tue Sep 17, 2019 9:44 pm Nam basically on board with hrr, long day tomorrow and Thursday morning

The 00Z 12km NAM puts 25 inches at Jason's house!1!

srain, what’s the difference from 12km and 3km

The NAM 12km runs out to 84 hours. The 3km only runs out to 60 hours. The 3km is a "finer" resolution mesoscale model. One more tool in the tool box.

https://www.tropicaltidbits.com/analysi ... 91800&fh=3


Here is the 3km

srainhoutx wrote: ↑Tue Sep 17, 2019 9:47 pm

stormlover wrote: ↑Tue Sep 17, 2019 9:44 pm Nam basically on board with hrr, long day tomorrow and Thursday morning

The 00Z 12km NAM puts 25 inches at Jason's house!1!

I just saw that. I wondered if you were still up I'm watching this and the Astros-Rangers on TV.

Definitely a fluid situation. I had 28" during Harvey and did not flood; no houses in Imperial Oaks flooded either. But still, would not be good for some of my neighbors if that verified. Parts of Rayford are notorious for flooding.

There must be absolute zero steering currents.

jasons wrote: ↑Tue Sep 17, 2019 9:54 pm

srainhoutx wrote: ↑Tue Sep 17, 2019 9:47 pm

stormlover wrote: ↑Tue Sep 17, 2019 9:44 pm Nam basically on board with hrr, long day tomorrow and Thursday morning

The 00Z 12km NAM puts 25 inches at Jason's house!1!

I just saw that. I wondered if you were still up

Definitely a fluid situation. I had 28" during Harvey and did not flood; no houses in Imperial Oaks flooded either. But still, would not be good for some of my neighbors if that verified. Parts of Rayford are notorious for flooding.

I measured just shy of 48 inches here for Harvey. The water never rose above the curb for the duration. Tax Day was a totally different story, although we sit high and dry.

Update from Jeff and I am out of here for the night...

Center of tropical depression Imelda located over southwest Harris County near Bellaire moving toward the N at 7mph.

Heaviest rainfall has focused well to the south of the center over central Brazoria County this evening where 4-5 inches of rain has fallen. Additionally 24 hour rainfall totals of 3-6 inches have occurred in SE Harris County with 2-3 of those inches falling in the last 2-3 hours. Grounds are now saturated in the SE portions of Harris County and run-off in those areas is becoming maximized. Luckily, short duration rainfall totals have been on the order of 1-2 inches per hour at the most which is prevent any urban flooding thus far.

The center of Imelda will continue toward the north overnight and into northern Harris and southern Montgomery Counties by early Wednesday morning. Heaviest rains will likely focus to the east and south of the center or generally along and east of the I-45/SH 288 corridor. Additional rainfall amounts of 2-4 inches will be possible by sunrise Wednesday morning with isolated higher totals. Most of this will likely be able to be handled in the creeks and bayous.

Channel Conditions:

Turkey Creek is within 3 ft of bankfull at FM 1959

Clear Creek, Armand Bayou, and Beamer Ditch are all elevated from the rainfall this evening, but within banks.

All other channels are well within their banks.

On a side note, I'm glad to see so many people active today. It is great so see so many long term members on today and so many people involved. Thanks, everyone for all the great information!

Also, keep in mind that a lot of that rain for Harvey fell over the first 3 days. This looks like it might be quicker in some places.

My view from Bellaire as the center passed overhead.
https://twitter.com/stephenuzick/status ... 98791?s=21

Has to be at least 6” here in Friendswood.
We’ve been in the yellow for 2 hours already.

6.95" so far in Danbury

So far, the situation has been very manageable. Thank goodness. We need to keep a close watch, however, as things could turn very quickly. We know the drill.

I just drove from the east end of houston down 288 to angleton...man talk about scary! Thay rain was coming down so hard and fast..angleton is starting to flood on some streets

D-MAX not too far away.

It's definitely opening-up. What's left of the original LLC has now rotated SW to Rosenburg, but that's now rotating around a broader center near Westchase along BW8.

On another note - it's almost surreal - watching the Astros game. Minute Maid park is business-as-usual - hard to believe a Tropical Storm made landfall today in Freeport.

Looking at radar doesnt seem like much is left

The Astros game just finished up. I hope everybody is able to make it home safely.

https://twitter.com/NWSWPC/status/1174154051270979586
https://origin.wpc.ncep.noaa.gov/metwat ... 61&yr=2019

Mesoscale Precipitation Discussion 0861
NWS Weather Prediction Center College Park MD
1048 PM EDT Tue Sep 17 2019

Areas affected...Upper Texas Coast and Houston Metro

Concerning...Heavy rainfall...Flash flooding likely

Valid 180247Z - 180847Z

Summary...A potentially significant flash flood event along the
upper Texas coast and Houston metro may setup from late this
evening and overnight. Hourly totals in excess of 2" with totals
through 4 AM CDT 3-6" are likely. Isolated totals through 4 AM CDT
of 6-8" are possible.

Discussion...As of 0230Z, the latest estimated position of TD
Imelda was west/southwest of Houston per recent observations and
radar imagery. Radar shows several training rain bands spiraling
onshore. In the last 6 hours, widespread 2-4" totals have been
observed, from mainly the south Houston metro toward the Galveston
coastal areas and near Freeport. In the last 18-24 hours,
widespread 4-6" totals have been observed with local maxes in the
6-7" range. All of this rain today has primed and conditioned the
soils, resulting in a much lower flash flood guidance.

A potentially significant flash flood event may setup overnight in
and around the Houston metro as the environmental conditions
remain more than sufficient for long duration heavy rain. PWs
analyzed from the 00Z soundings and blended TPW products were 2.2
to 2.4". The most recent mesoanalysis also showed favorable
instability in the region, especially from Houston eastward where
MUCAPE of 2000-2500 J/kg exists. With warm cloud depths well above
4 km, extremely efficient rain producing thunderstorms are
expected. Through the overnight, there will be a narrow axis where
the best moisture convergence overlaps with the favorable
instability and higher PWs, generally east/southeast of the low
center as it drifts north/northeast. This puts the greater Houston
metro area in this axis, further highlighting the potentially
significance.

The most recent hi-res models have a fairly tight cluster of 3-6"
totals through 4 AM CDT with some CAMs showing isolated 8" totals
(high-end scenario). The most recent HREF probabilities show
moderate probabilities of 1-hr totals exceeding 2-3" from around
the Houston area toward the Galveston coast.

All told, the combination of slow-moving TD Imelda with the
extreme environmental conditions for heavy rainfall over a highly
urban area could result in significant flash flood event. This
situation will continue to be monitored through the night.

Taylor

ATTN...WFO...HGX...LCH...

ATTN...RFC...WGRFC...

LAT...LON 30789504 30559466 30189419 29739405 29549433
29379464 29199502 28909539 28669589 29209590
29379555 29949586 30409585 30649566

Red returns moving into downtown HOU. With a static storm, entraining and core rain possible as the night wears on.