Alert archive / Colorado / Flash Flood Watches in 2008

Flash Flood Watch 3, NWS Denver/Boulder, CO

August 7, 200813 counties in Colorado

NWS Denver/Boulder, CO issued this flash flood watch at Aug 7, 2008, 11:37 AM MDT for 13 counties in Colorado. It took effect at Aug 7, 2008, 12:00 PM MDT. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued: Aug 7, 2008, 11:37 AM MDT (17:37 UTC)
In effect from: Aug 7, 2008, 12:00 PM MDT
Expired: Aug 7, 2008, 7:15 PM MDT
In force: 7 hr
Issued by: NWS Denver/Boulder, CO
Flood severity: None

Counties Adams County, CO, Arapahoe County, CO, Boulder County, CO, Broomfield County, CO, Clear Creek County, CO, Denver County, CO, Douglas County, CO, Elbert County, CO, Gilpin County, CO, Jefferson County, CO, Larimer County, CO, Park County, CO, Weld County, CO

The radar

The Denver radar (KFTG), 39 km from the middle of the area, began a volume at 17:38 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

Denver, CO (KDNR), launched 12:00Z, 5.6 hours before the alert went out and 151 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 841 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: -6 m²/s²
0-3 km storm-relative helicity: -12 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 Aug 7, 10:40 AM MDT, 57 minutes earlier.

Area forecast discussion, Aug 7, 10:40 AM MDT, 57 minutes before

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Hazardous weather outlook, Aug 7, 11:21 AM MDT, 16 minutes before

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In the hours before

Local storm report, Aug 7, 9:24 AM MDT, 2 hours 13 minutes before

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Local storm report, Aug 7, 10:06 AM MDT, 1 hour 31 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 6, 6:00 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Elbert	45 min
Aug 6, 6:18 PM MDT	Areal Flood Advisory	BOU	Weld	87 min
Aug 6, 6:22 PM MDT	Areal Flood Advisory	BOU	Douglas, Elbert	83 min
Aug 6, 6:26 PM MDT	Areal Flood Advisory	BOU	Arapahoe, Elbert	94 min
Aug 6, 6:30 PM MDT	Tornado Warning	BOU	Douglas, Elbert	30 min
Aug 6, 6:39 PM MDT	Tornado Warning	BOU	Adams, Broomfield, Denver, Weld	36 min
Aug 6, 6:47 PM MDT	Areal Flood Advisory	BOU	Broomfield, Weld	88 min
Aug 6, 6:59 PM MDT	Tornado Warning	BOU	Boulder, Larimer, Weld	31 min
Aug 6, 7:20 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Boulder, Broomfield, Denver, Jefferson and 1 more	85 min
Aug 6, 7:32 PM MDT	Flash Flood Warning	BOU	Weld	3 hr
Aug 6, 7:36 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Denver, Elbert, Lincoln, Morgan and 2 more	3 hr
Aug 6, 8:56 PM MDT	Areal Flood Advisory	BOU	Morgan, Washington	109 min
Aug 6, 9:50 PM MDT	Flash Flood Warning	BOU	Morgan, Washington	85 min
Aug 6, 10:30 PM MDT	Areal Flood Advisory	BOU	Washington	90 min
Aug 6, 10:48 PM MDT	Areal Flood Advisory	BOU	Weld	87 min

Nearby

Flash Flood Watches in Colorado, 2008 Every flash flood watch in 2008

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.