Extended Outlook Issued 4-13-2011

Below is 500 mb map (at 18,0000 feet) for the period April 20 to April 26. There is a flat ridge of high pressure over the Northwest. Also notice a trough of low pressure near the Gulf of Alaska and this feature will tend to bring weather systems into the Northwest. The bottom line message weather wise is above average precipitation and average to below average temperatures for this period