Alert archive / Colorado / Flash Flood Watches in 2017
Flash Flood Watch 3, NWS Grand Junction, CO
NWS Grand Junction, CO issued this flash flood watch at Jul 21, 2017, 2:52 AM MDT for 18 counties in Colorado; 4 counties in Utah. It took effect at Jul 21, 2017, 12:00 PM MDT. It was in force for 12 hr.
The area
The counties it named.
The facts
- Issued
- Jul 21, 2017, 2:52 AM MDT (08:52 UTC)
- In effect from
- Jul 21, 2017, 12:00 PM MDT
- Expired
- Jul 22, 2017, 12:00 AM MDT
- In force
- 12 hr
- Issued by
- NWS Grand Junction, CO
- Flood severity
- None
All 22 counties
Archuleta County, CO, Delta County, CO, Dolores County, CO, Eagle County, CO, Garfield County, CO, Gunnison County, CO, Hinsdale County, CO, La Plata County, CO, Mesa County, CO, Moffat County, CO, Montezuma County, CO, Montrose County, CO, Ouray County, CO, Pitkin County, CO, Rio Blanco County, CO, Routt County, CO, San Juan County, CO, San Miguel County, CO, Daggett County, UT, Grand County, UT, San Juan County, UT, Uintah County, UT
The radar
The Grand Junction radar (KGJX), 32 km from the middle of the area, began a volume at 08:55 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Salt Lake City I, UT (KSLC), launched 00:00Z, 8.9 hours before the alert went out and 393 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 783 J/kg
- Mixed-layer CIN
- -21 J/kg
- Mixed-layer LCL
- 2771 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 26 m²/s²
- 0-3 km storm-relative helicity
- 107 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
What forecasters said that day
The local office's own words before this flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Grand Junction, CO wrote its last area forecast discussion before this flash flood watch went out at Jul 20, 4:55 PM MDT, 9 hours 57 minutes earlier.
Area forecast discussion, Jul 20, 4:55 PM MDT, 9 hours 57 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<body>
<main class="wrap">
<section class="card" role="status" aria-live="polite">
<div class="status" id="status">Temporary Notice</div>
<h1 id="headline">This service is currently unavailable.</h1>
<p id="message1">
The site you requested is temporarily down for maintenance or an unexpected outage.
</p>
<p id="message2">
Please try again in a few minutes.
</p>
<p class="small" id="detail">
If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>Hazardous weather outlook, Jul 20, 4:16 AM MDT, 22 hours 36 minutes before
Hazardous Weather Outlook National Weather Service GRAND JUNCTION CO 416 AM MDT Thu Jul 20 2017 COZ003-006>009-011-017-020>022-UTZ022-025-027>029-211030- Roan and Tavaputs Plateaus-Grand Valley-Debeque to Silt Corridor- Central Colorado River Basin-Grand and Battlement Mesas- Central Gunnison and Uncompahgre River Basin- Uncompahgre Plateau and Dallas Divide- Paradox Valley/Lower Dolores River- Four Corners/Upper Dolores River-Animas River Basin- Southeast Utah-Tavaputs Plateau-Arches/Grand Flat- La Sal and Abajo Mountains-Canyonlands/Natural Bridges- 416 AM MDT Thu Jul 20 2017 This hazardous weather outlook is for portions of northwest Colorado...southwest Colorado...west central Colorado...east central Utah and southeast Utah. .DAY ONE...Today and Tonight A flash flood watch is in effect for the area this afternoon through midnight tonight. Monsoonal moisture remains in place and will bring an increase in thunderstorm coverage by the afternoon. Flooding due to heavy rainfall rates will become more likely, especially over areas that are already saturated from recent rainfall. Some storms will also be capable of producing gusty outflow winds but every storm will have the potential to create dangerous cloud to ground lightning. .DAYS TWO THROUGH SEVEN...Friday through Wednesday Moisture shifts eastward with potential for heavy rainfall lasting through Friday. Some drier air works in from the northwest on Saturday for a downturn in storm activity this weekend into early next week. Another surge of moisture moves in by the middle of next week, increasing the thunderstorm coverage. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed. COZ001-002-004-005-010-012>014-018-019-023-UTZ023-024-211030- Lower Yampa River Basin-Central Yampa River Basin- Elkhead and Park Mountains-Upper Yampa River Basin- Gore and Elk Mountains/Central Mountain Valleys- West Elk and Sawatch Mountains-Flat Tops- Upper Gunnison River Valley-Northwest San Juan Mountains- Southwest San Juan Mountains-San Juan River Basin- Eastern Uinta Mountains-Eastern Uinta Basin- 416 AM MDT Thu Jul 20 2017 This hazardous weather outlook is for portions of northwest Colorado...southwest Colorado...west central Colorado and northeast Utah. .DAY ONE...Today and Tonight Monsoonal moisture remains in place and will bring an increase in thunderstorm coverage by the afternoon. Localized flooding due to heavy rainfall rates will become more likely, especially over areas that are already saturated from recent rainfall. Some storms will also be capable of producing gusty outflow winds but every storm will have the potential to create dangerous cloud to ground lightning. .DAYS TWO THROUGH SEVEN...Friday through Wednesday Moisture shifts eastward with potential for heavy rainfall lasting through Friday. Some drier air works in from the northwest on Saturday for a downturn in storm activity this weekend into early next week. Another surge of moisture moves in by the middle of next week, increasing the thunderstorm coverage. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed.
The office that day
Everything else NWS Grand Junction, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 6:25 PM MDT | Special Weather Statement | GJT | Montezuma | 35 min |
| Jul 20, 6:41 PM MDT | Special Weather Statement | GJT | Rio Blanco | 49 min |
| Jul 21, 1:53 PM MDT | Areal Flood Advisory | GJT | Garfield, Mesa | 3 hr |
| Jul 21, 2:20 PM MDT | Special Weather Statement | GJT | Moffat | 40 min |
| Jul 21, 2:34 PM MDT | Special Weather Statement | GJT | Moffat | 41 min |
| Jul 21, 2:42 PM MDT | Areal Flood Advisory | GJT | Moffat | 3 hr |
| Jul 21, 3:21 PM MDT | Special Weather Statement | GJT | Dolores | 24 min |
| Jul 21, 4:47 PM MDT | Special Weather Statement | GJT | Mesa | 43 min |
| Jul 21, 4:48 PM MDT | Special Weather Statement | GJT | Rio Blanco | 42 min |
| Jul 21, 5:12 PM MDT | Areal Flood Advisory | GJT | Mesa | 3 hr |
| Jul 20, 11:03 PM MDT | Special Weather Statement | GJT | Daggett | 42 min |
| Jul 21, 1:33 AM MDT | Areal Flood Advisory | GJT | Daggett, Uintah | 3 hr |
| Jul 21, 12:55 PM MDT | Areal Flood Advisory | GJT | Grand, Uintah | 3 hr |
| Jul 21, 5:01 PM MDT | Special Weather Statement | GJT | Grand | 44 min |
| Jul 21, 5:24 PM MDT | Areal Flood Advisory | GJT | Grand | 5 hr |
Nearby
Flash Flood Watches in Colorado, 2017Flash Flood Watches in Utah, 2017Every flash flood watch in 2017
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.