7 to 10 day Northwest Weather and July 4

Current numerical forecast models are indicating that the weather through July 4, 2011 is below normal rainfall and average temperatures. Some of the extended forecast models out to July 9 indicate a trough of low pressure that returns close to July 9 so cooler conditions and chance of some showers will return.
The map below indicates a trough of low pressure off the coast on July 9. Map below is 500 mb chart for the 18,000 to 19,000 foot level.
http://www.ecmwf.int/products/forecasts/d/charts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!240!North%20America!pop!od!oper!public_plots!2011062900!!/

7 to 10 Day Weather for the Washington Cascades

The general forecast is for below normal temperatures as we will continue the pattern of an active storm track over the Pacific Northwest. Basically troughs of low pressure and the associated surface lows will drop down from the north to bring cooler conditions at times with some precipitation.

The map below depicts the pattern that we will have over the 7 to 10 day period. The map below is the mean position of the 500 mb map which at about 18,000 to 19,000 foot level. This map is for the period June 28 to July 4 and indicates a trough of low pressure off the coast of Washington. The bottom line with this pattern is below normal temperatures so the Northwest will continue the same pattern that has been in place over the last several months, cooler than normal. However with this pattern there will be some brief periods that will be sunny conditions and average temperatures.
Finally on the map below the green contour lines are the heights which the pressure is at 500 mb. So the line of 5700 is in meters or is 18,810 feet.
When does summer usually start, July 5. We will see if that happens again this year.

10 day weather forecast Pacific Northwest

Map below is 500 mb level (at about 19,000 feet) and is average position for June 22 through June 28. Of note is the trough of low pressure off the coast of Washington and this has been a typical pattern that we have seen for much of the last several months. The bottom line weather will be temperatures will tend to be below normal, however we can have some brief periods of temperatures close to normal.

7 to 10 weather forecast Cascades and Northwest

Map below is the average position of the 500 mb map (at about 18,000 foot level) for the June 12 to June 18 period. This map indicates a zonal pattern (westerly flow) into the Cascades and the rest of the Pacific Northwest. This type of pattern will generally bring average temperatures and close to average precipitation. However, lower confidence in this extended forecast as the models have been inconsistent lately.

7 to 10 day weather trends for the NW

The map below is the 500 mb chart (for about 19,000 feet) for Saturday June 11. Notice the strong trough of low pressure off the Washington Coast and this frankly looks more like a winter type of pattern. This is the general pattern that we will have for some of June, cool and wet. However for this weekend Saturday June 4 through Monday June 6 we should have a period of some warm temperatures and dry conditions. For Seattle for the month of May precipitation was 180% of normal and temperatures were 3.5 F degrees below normal. Looks like June will follow this pattern.

Contest Guess how much snow at Mt. Rainier Paradise Ranger on June 19, 2011. Go to this web site to enter contest and and see rules. Must have guesses by by early Saturday June 4
http://www.snohomish.org/index.php?page_id=597
The winner gets two of Craig Romano's new books on the North and Central Cascades.