National Situation Update: Wednesday, April 13, 2011

Significant National Weather

WestA low pressure system will generate a variety of inclement weather across the Central Great Basin.  Snow showers will continue into the evening with snowfall amounts of one or two inches in the valleys.  Isolated thunderstorms are forecast across portions of Nevada with wind gusts of up to 50 mph.  Also, Critical Fire Weather conditions are forecast across southeast Arizona, southern New Mexico and west Texas throughout the day, due to low relative humidity and gusty winds.

MidwestIsolated thunderstorms are forecast from eastern Wyoming to the Great Lakes.  Tonight, an area of low pressure will move through the Central Plains bringing snow to northeast Wyoming and most South Dakota. Several inches of snow will be possible, with the heaviest snowfall over central South Dakota.
SouthUnder an area of high pressure, most of the region will remain sunny and dry.  Red Flag Warnings will remain in effect through this evening for portions of the Florida Panhandle, southern Alabama and southern Georgia, due to low relative humidity and gusty winds.
NortheastA low pressure system moving across the Southern Appalachians will produce moderate to heavy rain as it moves northeastward into New England during the early morning.  Periods of light to heavy rain will continue this evening over most .  (National Weather Service, Hydrometeorological Prediction Center, and various media sources).

Potential Dam Failure in North Dakota

On April 12, the North Dakota State Water Commission reports erosion has been observed at Burlington #1 Dam on the Des Lacs River in Ward County in north central North Dakota. This extra strain has increased the threat of a possible dam failure. There is a moderate to high risk that this dam will fail within the next 24 hours and personnel monitoring the dam were removed for safety reasons.
Based on worst case scenario simulations, if the dam was to fail, residents below the dam should expect an additional 2 to 3 foot rise in Water Level.  Residents 1 mile below the dam will experience a 1.1 foot increase above current river stage values.  This level will likely continue to the confluence between the Des Lacs and the Mouse (Souris).
Local authorities have issued an evacuation order for approximately 50 -100 residences. The ND National Guard and the Game and Fish Department have prepositioned equipment in Minot, ND in anticipation of potential response operations.  Also, the Governor has requested that Ward County be added to the Emergency Declaration (FEMA-3318-EM-ND), since the dam is owned and operated by the county.  There are no additional requests for FEMA assistance.

Midwest Spring Flooding

Major to minor flooding continues across many of the rivers in the Upper Midwest.

Earthquake Activity

On April 13, at 12:28 a.m., EDT, a 5.1 magnitude earthquake occurred 124 miles east-northeast of San Juan, PR at a depth of 19.3 miles.  No damages or injuries have been reported and no tsunami was generated.   (USGS)

Fire Activity

Tuesday, April 12, 2011

• National Preparedness Level: 1
• Initial attack activity: Moderate (324 new fires)
• New Large Fires: 7
• Large Fires Contained: 6
• Uncontained Large Fires: 19
• Type 1 IMTs Committed: 1
• Type 2 IMTs Committed: 0
• States affected: CO, NM, TX, OK, MO, GA, KS and FL (NIFC)

Wildfire Activity
Rockhouse Fire (Presido County, TX)
On April 9, a FMAG was approved for the Rockhouse Fire in Presidio County.  As of April 12, the fire had burned approximately 108,000 acres and was 60 percent contained. A Type I Incident Management Team assumed command of the fire on April 12.

Disaster Declaration Activity

No new activity Amendment No. 1 to FEMA-1961-DR-MO was approved on April 11, adding Camden County for Public Assistance.(FEMA HQ)