We want to hear from you. Please tell us how we can better serve you by taking this survey.
x

Boulder's 1-in-100 Year Flood Diminishing; Ingrid a Dangerous Flood Threat for Mexico

By: Dr. Jeff Masters , 3:43 PM GMT on September 13, 2013

Colorado's epic deluge is finally winding down, as a trough of low pressure moves across the state and pushes out the moist, tropical airmass that has brought record-breaking rainfall amounts and flooding. Devastating flash floods swept though numerous canyons along the Front Range of Colorado's Rocky Mountains Wednesday night and Thursday morning, washing out roads, collapsing houses, and killing at least three people. The flood that swept down Boulder Creek into Boulder, Colorado was a 1-in-100 year event, said the U.S. Geological Survey. A flash flood watch continues through noon Friday in Boulder. According to the National Weather Service, Boulder's total 3-day rainfall as of Thursday night was 12.30". Based on data from the NWS Precipitation Frequency Data Server, this was a greater than 1-in-1000 year rainfall event. The city's previous record rainfall for any month, going back to 1897, was 9.59", set in May 1995. Some other rainfall totals through Thursday night include 14.60" at Eldorado Springs, 11.88" at Aurora, and 9.08" at Colorado Springs. These are the sort of rains one expects on the coast in a tropical storm, not in the interior of North America! The rains were due to a strong, slow-moving upper level low pressure system to the west of Colorado that got trapped to the south of an unusually strong ridge of high pressure over Western Canada. This is the same sort of odd atmospheric flow pattern that led to the most expensive flood disaster in Canadian history, the $5.3 billion Calgary flood of mid-June this summer. The upper-level low responsible for this week's Colorado flood drove a southeasterly flow of extremely moist tropical air from Mexico that pushed up against the mountains and was lifted over a stationary front draped over the mountains. As the air flowed uphill and over the front, it expanded and cooled, forcing the moisture in it to fall as rain. Balloon soundings from Denver this morning continued to show levels of September moisture among the highest on record for the station, as measured by the total Precipitable Water (PW), which is how much water would fall at the ground if the entire amount of water vapor through the depth of the atmosphere was condensed. Four of the top eight all-time September highs for Precipitable Water since records began in 1948 have been recorded over the past two days:

1.33" 12Z September 12, 2013
1.31" 00Z September 12, 2013
1.24" 12Z September 13, 2013
1.23" 12Z September 10, 1980
1.22" 00Z September 2, 1997
1.21" 00Z September 7, 2002
1.20" 00Z September 13, 2013

Wunderground weather historian Christopher C. Burt discusses how this year's flood compares to previous Colorado floods in his latest post.

A map of Boulder flood zones and detailed history of previous floods in the area may be found here.


Figure 1. A torrent of water rushes alongside a swamped house following flash flooding near Left Hand Canyon, south of Lyons, Colo., Sept 12, 2013. (AP Photo/Brennan Linsley)



Figure 2. Observed rainfall for the Colorado's Front Range from the September 11 - 13 rain event. Rainfall amounts greater than 10" (pink colors) were indicated near Boulder. Image credit: NWS Denver.

Tropical Storm Ingrid a Dangerous Rainfall Threat for Mexico
Tropical Storm Ingrid, the ninth named storm of the 2013 Atlantic hurricane season, has formed in the Southwestern Gulf of Mexico's Bay of Campeche. Ingrid is the most dangerous Atlantic tropical cyclone of 2013 thus far, due to its rainfall potential. Ingrid is embedded in an exceptionally moist environment, and is already bringing heavy rains to the Mexican coast in Veracruz state, as seen on Mexican radar. Satellite loops show that Ingrid is not well-organized, and has only a modest area of heavy thunderstorms. However, the Friday morning hurricane hunter mission found 45 mph winds, prompting NHC to upgrade Ingrid. Moderate wind shear of 15 - 20 knots is interfering with development, but ocean temperatures are a very warm 29 - 29.5°C (84 - 85°F).


Figure 3. Percent chance of receiving more than 16" of rain during a five day period, from the Friday 2 am EDT run of the experimental GFDL ensemble model for Tropical Storm Ingrid. More than 16" of rain are predicted for the Oaxaca and Tampico areas of Mexico. Image credit: NOAA/GFDL.

Forecast for Ingrid
The soils along the Mexican Gulf Coast are already saturated from the rains of Tropical Depression Eight and Tropical Storm Fernand, and it won't take much additional rain to generate dangerous flash floods and mudslides. An added danger is the presence of tropical disturbance 90E in the Eastern Pacific Ocean, on the other side of Mexico. If Ingrid intensifies sufficiently, it could draw in the moisture from 90E across Southern Mexico, resulting in torrential rains on both the Pacific and Atlantic sides of Southern Mexico. Ninety-E represents a threat to develop into a tropical depression in its own right; in their 8 am EDT Friday Tropical Weather Outlook, NHC gave 2-day odds of development of 70% for the disturbance, and predicted a north to northwest motion of the storm towards the coast. This morning's 2 am EDT run of the experimental GFDL ensemble model predicted that a some areas of Mexico are at high risk of 16+ inches of rain due to the combined effects of Ingrid and 90E. The greatest danger is on the Pacific side in Oaxaca state, where the combined effects of the circulations of Ingrid and 90E will pull a flow of very moist air upwards over the mountains, creating torrential rains. All of the models predict a west-northwest to northwest track for Ingrid into Mexico, but heavy rains of 2 - 4" may also affect extreme South Texas by early next week.

Today is the 25th anniversary of the intensification of Hurricane Gilbert into the strongest hurricane ever observed in the Atlantic (at the time.) I was on the hurricane hunter flight into Gilbert that day, and will be posted an account of the mission later today.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

Sign In or Register Sign In or Register

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 538 - 488

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35Blog Index

989mb 48 minutes after 999 at the 5PM update....
What?
Member Since: Posts: Comments:
Quoting 532. Envoirment:


Might be a contaminated reading?
Doesn't seem like it.

212230 1919N 09507W 7569 02372 9929 +156 +135 141035 035 040 000 00
212300 1917N 09508W 7570 02369 9923 +160 +129 138033 034 039 000 00
212330 1916N 09510W 7596 02335 9918 +165 +121 134032 032 035 001 00
212400 1915N 09512W 7559 02377 9910 +169 +114 130029 030 033 000 03
212430 1913N 09513W 7526 02413 9901 +174 +114 140026 026 031 001 00
212500 1912N 09514W 7513 02424 9892 +180 +113 145023 025 031 000 03
212530 1911N 09516W 7531 02399 9890 +179 +122 146016 018 023 001 00
212600 1909N 09518W 7513 02421 9897 +170 +123 142009 013 016 000 00
212630 1908N 09520W 7584 02339 9906 +162 +133 344003 005 015 001 00
212700 1907N 09521W 7537 02392 9913 +153 +130 311006 007 016 000 03
212730 1908N 09523W 7548 02382 9918 +149 +129 344008 010 017 000 03
212800 1910N 09523W 7538 02395 9925 +144 +123 006010 011 019 000 00
212830 1912N 09523W 7530 02402 9922 +147 +120 042012 014 018 001 00
212900 1914N 09523W 7525 02410 9918 +154 +116 062016 017 022 001 00
212930 1916N 09523W 7566 02368 9917 +159 +123 070016 018 025 000 00
213000 1918N 09523W 7564 02372 9918 +162 +119 077015 016 026 000 00
213030 1920N 09523W 7551 02389 9922 +159 +118 084021 023 027 000 00
Member Since: August 1, 2012 Posts: 0 Comments: 449
Gabrielle

Member Since: Posts: Comments:
Quoting 533. DonnieBwkGA:


In Nova Scotia too. Pressures at some stations are already below 1002 mb vs the 1004 pressure given at Gabby's final advisory.

Gabrielle blowing her horn?


Haha, which part?
Member Since: Posts: Comments:
.
Member Since: Posts: Comments:
Quoting 524. maxgerhe:
Time: 21:25:30Z
Coordinates: 19.1833N 95.2667W
Acft. Static Air Press: 753.1 mb (~ 22.24 inHg)
Acft. Geopotential Hgt: 2,399 meters (~ 7,871 feet)
Extrap. Sfc. Press: 989.0 mb (~ 29.21 inHg)
D-value: -
Flt. Lvl. Wind (30s): From 146° at 16 knots (From the SE/SSE at ~ 18.4 mph)
Air Temp: 17.9°C (~ 64.2°F)
Dew Pt: 12.2°C (~ 54.0°F)
Peak (10s) Flt. Lvl. Wind: 18 knots (~ 20.7 mph)
SFMR Peak (10s) Sfc. Wind: 23 knots (~ 26.4 mph)
SFMR Rain Rate: 1 mm/hr (~ 0.04 in/hr)
(*) Denotes suspect data

RI?


Might be a contaminated reading?
Member Since: Posts: Comments:
Humberto ..

Member Since: Posts: Comments:
Very happy to see that Mark Sudduth had a very positive post > " As for the long range…things look really good. The global models were indicating more development in the Caribbean or Gulf but have backed off dramatically as of late. With a strong cold front pushing south this weekend, a true taste of fall is coming and should keep any tropical mischief well out to sea if coming from the east.

We will have to certainly keep an eye on the Caribbean and Gulf of Mexico since those areas are favored this time of year and through October. It is at least encouraging for coastal interests to see nothing in the long range that could threaten the good luck that we have had this season. If we can manage just a few more weeks, we might just make it out with hardly a scratch, at least in the United States.". For sure, that would be fantastic news for all of us East & Gulf Coasters.
Member Since: Posts: Comments:
Quoting 525. VR46L:


They really are very close . and Manu seems to be in better shape . I think ingie is in trouble


Disagree entirely.

Ingrid is the much more organized storm.
Member Since: Posts: Comments:
Big pressure drop.
Member Since: Posts: Comments:
Ingrid is quite deep for a tropical storm! Seems like it's living up to the curse of the I storm.
Member Since: Posts: Comments:
Quoting 517. allancalderini:
That was Gabrielle right?
Suprisingly, No. That's Humberto.
Member Since: August 18, 2011 Posts: 0 Comments: 994
525. VR46L
Quoting 521. allancalderini:
Those two are almost on top of each other.


They really are very close . and Manu seems to be in better shape . I think ingie is in trouble
Member Since: Posts: Comments:
Time: 21:25:30Z
Coordinates: 19.1833N 95.2667W
Acft. Static Air Press: 753.1 mb (~ 22.24 inHg)
Acft. Geopotential Hgt: 2,399 meters (~ 7,871 feet)
Extrap. Sfc. Press: 989.0 mb (~ 29.21 inHg)
D-value: -
Flt. Lvl. Wind (30s): From 146° at 16 knots (From the SE/SSE at ~ 18.4 mph)
Air Temp: 17.9°C (~ 64.2°F)
Dew Pt: 12.2°C (~ 54.0°F)
Peak (10s) Flt. Lvl. Wind: 18 knots (~ 20.7 mph)
SFMR Peak (10s) Sfc. Wind: 23 knots (~ 26.4 mph)
SFMR Rain Rate: 1 mm/hr (~ 0.04 in/hr)
(*) Denotes suspect data

RI?
Member Since: Posts: Comments:
need those folks on the ne windwds to get some rain go ex98
Member Since: September 11, 2010 Posts: 2 Comments: 6132
Quoting 517. allancalderini:
That was Gabrielle right?


No. Gabrielle is over Nova Scotia right now giving me some rain and a tiny bit of wind
Member Since: Posts: Comments:
Quoting 519. VR46L:
Those two are almost on top of each other.
Member Since: Posts: Comments:
This Ingid is already stronger than the last one..
:P
Member Since: Posts: Comments:
519. VR46L
Member Since: Posts: Comments:
Quoting 514. hurricanes2018:
notting left here!
That was Gabrielle right?
Member Since: Posts: Comments:
Quoting 488. GatorWX:
98L is still trying. Waiting for it to get near the the Bahamas... You never know!! :) Doubt the trough pulls it all the way out, we'll see.



Ingrid looks headed for southern BOC coast.



The direction that convection expands =/= movement. That's why satellite can be deceiving, recon and satellite both confirm Ingrid is stationary.
Member Since: July 8, 2005 Posts: 259 Comments: 25341

Quoting 513. Pensa2woodtx:
Looks like Ingrid will be a cat 2 heading north into middle tx then be pushed out by the front back into the GOM.Then head to Tampa florida. 55%
not sure...what?
Member Since: Posts: Comments:
notting left here!
Member Since: Posts: Comments:
Looks like Ingrid will be a cat 2 heading north into middle tx then be pushed out by the front back into the GOM.Then head to Tampa florida. 55%
Member Since: Posts: Comments:
Quoting 507. TropicalAnalystwx13:
As long as it remains stationary, it will be okay. The best solution for Mexico would be for it to run into land right now.

I hope it does.So the fail of the name Ingrid continues.
Member Since: Posts: Comments:
Let you all know a multiagency multi-aircraft mission (NASA, NOAA, and host of others) just flew today over and all in and out of Ingrid today as part of SEAC4RS. Its an incredible suite of instruments dissecting various weather this summer.

Link

Member Since: Posts: Comments:
I wonder what the pressure really is for Ingrid HH have it at 995
Member Since: Posts: Comments:
I was gone for 8 hours and everything happens -_- naturally.
Humberto is rapidly weakening.
Ingrid forms.
Gabrielle dissipates.
Manuel forms.
Wah..
Member Since: Posts: Comments:
Anyone else seeing Ingrid make a slight NW movement over the past couple frames?
Member Since: Posts: Comments:
As long as it remains stationary, it will be okay. The best solution for Mexico would be for it to run into land right now.

Member Since: Posts: Comments:
Quoting 480. PedleyCA:


Oh, goody.. More humidity headed our way.

sarc=on
Just the opposite here Ped, dew point has dropped 11 degrees to 39 in last 2hrs, shouldn't have any trouble hitting that mid 40s low tonight w/ it that low.
Member Since: Posts: Comments:
505. SLU
Member Since: Posts: Comments:
Goodnight.
Member Since: Posts: Comments:
Quoting 483. Sfloridacat5:


If Ingrid continues moving WNW at 12 mph its all over. Land interaction is already giving it issues.
You have the storms mixed up.
Member Since: Posts: Comments:
I'll post this again for all the comics in the house.

Got my storms confused. I'm the one that had just posted this information if a previous post about 5 minutes ago.

Ingrid
6 Hour Average Movement ( About ):
Toward the NW or 317%uFFFD
At 1.4 knots (1.6 mph | 2.6 km/h)

12 Hour Average Movement (About):
Toward the WSW or 248%uFFFD
At 4.6 knots (5.2 mph | 8.4 km/h)
Member Since: Posts: Comments:
Member Since: Posts: Comments:
Member Since: Posts: Comments:
The "Other side" of Ingrid - Manuel

Member Since: Posts: Comments:
Quoting 483. Sfloridacat5:


If Ingrid continues moving WNW at 12 mph its all over. Land interaction is already giving it issues.

That is Humberto's advisory you're looking at, Ingrid is stationary.
EDIT: Just saw your correction. :P

...INGRID DRENCHING PORTIONS OF EASTERN MEXICO...


SUMMARY OF 400 PM CDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...19.2N 95.4W
ABOUT 50 MI...85 KM E OF VERACRUZ MEXICO
ABOUT 180 MI...290 KM SE OF TUXPAN MEXICO
MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H
PRESENT MOVEMENT...STATIONARY
MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES
Member Since: Posts: Comments:
INGRID

CI# /Pressure/ Vmax
3.2 / 995.5mb/ 49.0kt


Final T# Adj T# Raw T#
3.2 3.4 3.4
Member Since: August 1, 2012 Posts: 0 Comments: 449
Quoting 488. GatorWX:
98L is still trying. Waiting for it to get near the the Bahamas... You never know!! :) Doubt the trough pulls it all the way out, we'll see.



Ingrid looks headed for southern BOC coast.



Ingrid isn't headed anywhere right now.
Member Since: Posts: Comments:
Quoting 483. Sfloridacat5:


If Ingrid continues moving WNW at 12 mph its all over. Land interaction is already giving it issues.


Good thing that it's Humberto moving WNW at 12 mph and not Ingrid then, huh?
Member Since: Posts: Comments:
I'm confused about the bolded line in the discussion on Ingrid.
INGRID IS CURRENTLY TRAPPED IN THE SOUTHERN BAY OF CAMPECHE AND THE
MODELS SUGGEST THAT THE CYCLONE WILL MOVE ERRATICALLY FOR THE NEXT
6 TO 12 HOURS OR SO. AFTER THAT TIME...MOST OF GUIDANCE...PRIMARILY
THE GFS AND THE ECMWF FORECAST INGRID TO MOVE SLOWLY NORTHWARD FOR
THE NEXT 24 TO 36 HOURS. AS A MID-LEVEL RIDGE REDEVELOPS OVER
TEXAS...INGRID SHOULD MAKE A SHARP LEFT TURN TOWARD THE COAST OF
MEXICO AND THEN MOVE INLAND. THIS IS THE SCENARIO USED IN THE
OFFICIAL FORECAST AT THIS TIME...BUT I WILL NOT BE SURPRISED IF
INGRID NEVER GETS OUT OF THE SOUTHERN BAY OF CAMPECHE.
Member Since: Posts: Comments:
Quoting 491. Sfloridacat5:


I'm going off of this.


TROPICAL STORM HUMBERTO ADVISORY NUMBER 21
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092013
500 PM AST FRI SEP 13 2013

...HUMBERTO WEAKENING QUICKLY...


SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...25.0N 32.1W
ABOUT 815 MI...1310 KM NW OF THE CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 12 MPH...19 KM/HMINIMUM CENTRAL PRESSURE...996 MB...29.41 INCHES

Oh.
Member Since: Posts: Comments:
Quoting 486. 62901IL:

Ingrid is stationary.


I got my storms confused for a minute. Ingrid has been drifting slowly WSW to NW today.

Ingrid
6 Hour Average Movement ( About ):
Toward the NW or 317%uFFFD
At 1.4 knots (1.6 mph | 2.6 km/h)

12 Hour Average Movement (About):
Toward the WSW or 248%uFFFD
At 4.6 knots (5.2 mph | 8.4 km/h)
Member Since: Posts: Comments:
490. VR46L
Quite alot going on in this image ... Make the most of it folks !

Member Since: Posts: Comments:
Quoting 483. Sfloridacat5:


If Ingrid continues moving WNW at 12 mph its all over. Land interaction is already giving it issues.
Umm...that's Humberto. Ingrid is currently, at least according to the NHC, Stationary, though it is predicted to be moving erratically for the next 6-12 hours. After that, it's expected to turn northwards.
Member Since: August 18, 2011 Posts: 0 Comments: 994
98L is still trying. Waiting for it to get near the the Bahamas... You never know!! :) Doubt the trough pulls it all the way out, we'll see.



Ingrid looks headed for southern BOC coast.

Member Since: Posts: Comments:

Viewing: 538 - 488

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35Blog Index

Top of Page

Dr. Jeff Masters' WunderBlog

About

Dr. Masters co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters from 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

JeffMasters's Recent Photos

Afternoon clouds over Southwest Puerto Rico
Storm clouds gathering over Half Dome
Sierra snow
snowman at Yosemite Falls