Wet Christmas

From the County: The National Weather Service in Seattle is predicting a very wet holiday period for Grays Harbor County. Rain will become steady and continue into Christmas day. There is a strong storm looming off the coast which according to forecast models, will travel to the North and impact Vancouver Island. This would be best for our outlook because it would only mean wind and rain. The Coast would receive a great deal more rain than inland areas for this Northern track. If the track follows a Southern route, it will bring large amounts of rain to the entire County and to the Olympics which in turn impacts the Satsop & Chehalis Rivers. Stay alert to the conditions daily.
Along with the rain, the County will also be susceptible to landslides. The ground is extremely saturated. Bluffs and steep hills along the coastal areas are areas to watch.

FORECAST

Tonight – Rain becoming steady. Sustained SE Winds will increase to 20-26mph along the coast.
Thursday & Thursday Night – Sustained SSE wind will increase to 30-34mph, gusting to 45mph. Steady Rain continuing.
Friday & Friday Night – SSE Winds steady at 29-36mph, gusting to 45mph. Steady rainfall.
Christmas Day – Rain tapering off to showers, winds diminishing.

Slow-moving Landslides—
What to do and look for during and
immediately after heavy rains

Areas that are generally prone to landslides:
4 On existing old landslides
4 On or at the base of slopes
4 In or at the base of minor drainage hollows
4At the base or top of an old fill slope
4At the base or top of a steep cut slope
4 Developed hillsides where leach field septic systems are used

Areas that are typically considered safe from landslides:
4 On hard, nonjointed bedrock that has not moved in the past
4 On relatively flat lying areas away from sudden changes in slope angle
4At the top or along the nose of ridges, set back from the tops of slopes

***  Features that might be noticed prior to major landsliding:  ***
4 Springs, seeps, or saturated ground in areas that have not typically been wet
4 New cracks or unusual bulges in the ground, street pavements, or sidewalks
4 Soil moving away from foundations
4Ancillary structures such as decks and patios tilting and (or) moving relative to the main house
4Tilting or cracking of concrete floors and foundations
4 Broken water lines and other underground utilities
4 Leaning telephone poles, trees, retaining walls, or fences
4 Offset fence lines
4 Sunken or down-dropped road beds
4 Rapid increase in creek water levels, possibly accompanied by increased turbidity (soil content)
4 Sudden decrease in creek water levels though rain is still falling or just recently stopped
4 Sticking doors and windows, and visible open spaces indicating jambs and frames out of plumb

What to do if you suspect imminent landslide danger:
1. Evacuate.
2. Contact your local fire, police, or public works department.
3. Inform affected neighbors.

Hydrologic Outlook
HYDROLOGIC OUTLOOK
WAC009-027-031-045-230100-

HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE SEATTLE WA
413 AM PST WED DEC 22 2010

…HEAVY PRECIPITATION POSSIBLE FOR THE OLYMPIC PENINSULA BEGINNING
THURSDAY…

WEATHER MODELS CONTINUE TO POINT TO A WET PERIOD BEGINNING
THURSDAY MORNING AND LASTING THROUGH SATURDAY MORNING FOR THE
OLYMPIC PENINSULA. A STALLED FRONTAL BOUNDARY OVER THE AREA ALONG
WITH STRONG SOUTHERLY FLOW AND RISING SNOW LEVELS WILL FOCUS HEAVY
RAINS ON THE SOUTH FACING SLOPES OF THE OLYMPIC RANGE.

WEATHER MODELS WERE STILL SHOWING A WIDE RANGE FOR PRECIPITATION
AMOUNTS OVER 48 HOURS BEGINNING THURSDAY MORNING AND ENDING
SATURDAY MORNING. ON THE LOW END…2 TO 4 INCHES COULD FALL…ON
THE HIGHER END…4 TO 6 INCHES COULD FALL.

AT THIS TIME…THE SKOKOMISH AND SATSOP…MAIN STEM RIVERS
FLOWING OFF THE SOUTH OLYMPICS…BEAR THE GREATEST RISK FOR
FLOODING SOME TIME LATE FRIDAY THROUGH EARLY SUNDAY.

STAY TUNED FOR FORECAST UPDATES.

Charles T Wallace
Deputy Director of Emergency Management
Grays Harbor County
(360) 249-3911 x 290
cwallace@co.grays-harbor.wa.us

http://www.co.grays-harbor.wa.us/info/DEM/Index.asp