Alert archive / Colorado / Flash Flood Watches in 2022

Flash Flood Watch 2, NWS Denver/Boulder, CO

July 24, 20229 counties in Colorado

NWS Denver/Boulder, CO issued this flash flood watch at Jul 24, 2022, 2:25 AM MDT for 9 counties in Colorado. It took effect at Jul 24, 2022, 11:00 AM MDT. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued
Jul 24, 2022, 2:25 AM MDT (08:25 UTC)
In effect from
Jul 24, 2022, 11:00 AM MDT
Expired
Jul 24, 2022, 7:57 PM MDT
In force
9 hr
Issued by
NWS Denver/Boulder, CO
Flood severity
None

Counties Boulder County, CO, Clear Creek County, CO, Gilpin County, CO, Grand County, CO, Jackson County, CO, Jefferson County, CO, Larimer County, CO, Park County, CO, Summit County, CO

The radar

The Denver radar (KFTG), 102 km from the middle of the area, began a volume at 08:29 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

Grand Junction, CO (KGJT), launched 00:00Z, 8.4 hours before the alert went out and 254 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.

Skew-T log-pSkew-T log-p diagram, Grand Junction, CO at 00:00Z on 2022-07-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Grand Junction, CO at 00:00Z on 2022-07-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 2 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
0 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
2 m²/s²
0-3 km storm-relative helicity
13 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

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 Denver/Boulder, CO wrote its last area forecast discussion before this flash flood watch went out at Jul 23, 9:38 PM MDT, 4 hours 47 minutes earlier.

Area forecast discussion, Jul 23, 9:38 PM MDT, 4 hours 47 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 23, 11:16 AM MDT, 15 hours 9 minutes before
Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1116 AM MDT Sat Jul 23 2022

COZ030>051-241730-
Jackson County Below 9000 Feet-
West Jackson and West Grand Counties Above 9000 Feet-
Grand and Summit Counties Below 9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet-
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Central and Southeast Park County-
Larimer County Below 6000 Feet/Northwest Weld County-
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield
County-
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County-
Elbert/Central and East Douglas Counties Above 6000 Feet-
Northeast Weld County-Central and South Weld County-Morgan County-
Central and East Adams and Arapahoe Counties-
North and Northeast Elbert County Below 6000 Feet/North Lincoln
County-
Southeast Elbert County Below 6000 Feet/South Lincoln County-
Logan County-Washington County-Sedgwick County-Phillips County-
1116 AM MDT Sat Jul 23 2022

This hazardous weather outlook is for northeast and north central
Colorado.

.DAY ONE...Today and Tonight

It is hot again today, however a cold front will move through all
the plains by mid afternoon. Scattered showers and thunderstorms
are expected for most of the forecast area this afternoon and
evening. They will produce a brief period of rain, lightning, and
gusty outflow winds to 50 mph. The strongest storms could produce
up to a half of an inch of rain in 30 minutes.  There is a low
threat of alpine burn area flash flooding.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

On Sunday, cooler temperatures and a higher coverage of showers
and storms can be expected. Some of the thunderstorms in the
mountains and near the Palmer Divide will produce locally heavy
rainfall. The threat of flash flooding in and near recent burn
areas will be elevated. Monday and Tuesday will be warmer and
drier, but there will still be a chance of afternoon and evening
thunderstorms both days. The threat of flash flooding in the burn
areas will be limited. By the middle of the week, it will be cooler
again with a better chance of showers and thunderstorms.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight.

RJK/Gimmestad

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 23, 6:37 PM MDTAreal Flood AdvisoryBOULarimer3 hr
Jul 23, 6:47 PM MDTAreal Flood AdvisoryBOUGrand3 hr
Jul 23, 7:50 PM MDTFlash Flood WarningBOUBoulder2 hr
Jul 24, 2:25 AM MDTFlood WatchBOUArapahoe, Douglas, Elbert, Lincoln, Washington18 hr
Jul 24, 1:37 PM MDTSpecial Weather StatementBOUBoulder38 min
Jul 24, 1:52 PM MDTSpecial Weather StatementBOUJefferson38 min
Jul 24, 2:16 PM MDTSpecial Weather StatementBOUAdams, Arapahoe44 min
Jul 24, 2:23 PM MDTFlash Flood WarningBOULarimer3 hr
Jul 24, 2:51 PM MDTSpecial Weather StatementBOUWeld39 min
Jul 24, 3:01 PM MDTSpecial Weather StatementBOUAdams, Arapahoe59 min
Jul 24, 3:06 PM MDTSpecial Weather StatementBOUMorgan39 min
Jul 24, 3:34 PM MDTAreal Flood AdvisoryBOUMorgan, Weld3 hr
Jul 24, 3:46 PM MDTSpecial Weather StatementBOUMorgan44 min
Jul 24, 3:55 PM MDTAreal Flood AdvisoryBOUDouglas3 hr
Jul 24, 4:22 PM MDTFlash Flood WarningBOUMorgan3 hr
Jul 24, 4:43 PM MDTSpecial Weather StatementBOUMorgan47 min
Jul 24, 5:10 PM MDTSpecial Weather StatementBOUWashington50 min
Jul 24, 5:36 PM MDTSevere Thunderstorm WarningBOUWashington39 min

Nearby

Flash Flood Watches in Colorado, 2022Every flash flood watch in 2022

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.