Wavy New Year

from the County:

POSSIBLE COASTAL FLOODING OVER NEW YEARS HOLIDAY

There is a projected forecast for coastal flooding due to one of the highest high tides of the year combined with high wind conditions, continued rainfall and large wave swells over the New Year’s Holiday. The first of two storm surges will happen around midday on Thursday and will coincide with one of the highest high tides of the year. Due to continued rainfall runoff added to coastal rivers, high winds (25-30MPH) and high wave heights (15-20 feet) along the beaches, the final water height above the higher than normal high tide could be 2-4 feet higher. The magnitude of the tidal situation is still uncertain, but the storm continues to track as a strong one.

Special Weather Statement

SPECIAL WEATHER STATEMENT

NATIONAL WEATHER SERVICE PORTLAND OR

NORTH OREGON COAST-CENTRAL OREGON COAST-SOUTH WASHINGTON COAST- INCLUDING THE CITIES OF…ASTORIA…CANNON BEACH…TILLAMOOK… LINCOLN CITY…NEWPORT…FLORENCE…RAYMOND…LONG BEACH…

…INCREASING THREAT FOR COASTAL FLOODING LATE THIS WEEK…

INCREASINGLY HIGH ASTRONOMICAL TIDES COMBINED WITH A POTENT PACIFIC STORM SYSTEM WILL BRING STRONG SOUTHERLY WINDS TO THE COAST AND THE POTENTIAL FOR COASTAL FLOODING TOWARD THE END OF THE WEEK. THE FIRST OF THESE STRONGER FRONTS IS EXPECTED TO MAKE LANDFALL MIDDAY THURSDAY WHICH COINCIDES WITH ONE OF THE HIGHEST HIGH TIDES OF THE YEAR.

A SECOND POWERFUL FRONT WILL SWING ON SHORE ON FRIDAY ALSO NEAR THE TIME OF HIGH TIDE. LARGE WESTERLY SWELL GENERATED BY THE STORM SYSTEM WILL ARRIVE AT THE COAST ON FRIDAY POSSIBLY GENERATING HAZARDOUS SURF CONDITIONS AS WELL AS ADDING TO THE COASTAL

FLOODING POTENTIAL.

AT TOKE POINT NEAR WILLAPA BAY…ASTRONOMICAL HIGH TIDES OF 11.1 FT WILL OCCUR AT THE MIDDAY TIDES THURSDAY AND FRIDAY. WATER LEVELS OVER 11 FT CREATE MINOR TIDAL OVERFLOWS WHILE 14.5 FT IS THE THRESHOLD FOR MORE WIDESPREAD COASTAL FLOODING PROBLEMS. THE MAGNITUDE OF TIDAL ANOMALY…THE ADDITIONAL BOOST TO THE COASTAL WATER LEVEL DUE TO THE ACTION OF FRONTAL SYSTEM ITSELF…IS STILL UNCERTAIN. HOWEVER IF THE STORM IS A STRONG ONE IT COULD ADD AN ADDITIONAL 2 TO 4 FEET TO THE BASE ASTRONOMICAL TIDE.

FACTORS THAT WILL INFLUENCE THE FINAL WATER HEIGHT INCLUDE…THE DEPTH OF THE LOW PRESSURE AREA AND STRENGTH OF THE WINDS…THE AMOUNT OF RUNOFF ADDED TO THE COASTAL RIVERS AND THE AMOUNT WAVE ACTION ALONG THE BEACHES TO DRIVE THE WATER FURTHER UP.

Charles T Wallace

Deputy Director of Emergency Management

Grays Harbor County

(360) 249-3911

cwallace@co.grays-harbor.wa.us