Rainy Season SLOWLY Fades Away

April 11, 2011

Does it ever feel like Spring progresses very slowly here in the Pacific Northwest?  You’re right!  The “wet season” (denoted by high probability of .01″ or more precipitation in any one day) peaks in late November, then stays quite high through February. 

The most obvious feature is the sudden ramp up in daily precipitation in the Fall (20% to 60% from early September to early November, or 2 months).  Then in the Spring, it takes DOUBLE that time to go from 60% back down to 20%.  That’s early March to early July.  So yes, it takes much longer to dry out in the Spring than turn wet in the Fall.  On the positive side, we go about 5 months with less than a 50% chance of rainfall on any one day.  That would be May through September.  On the negative side, our real dry period only lasts about 6-8 weeks.  It sometimes seems longer at the time (it’s TOO HOT!), but really never lasts more than 8-10 weeks even in the hottest/driest years.  This is the period in which I like to take the majority of my vacation time as well, for obvious reasons.  I could work every day from November through January, as long as I get those weeks in midsummer off!  Luckily that lines up with our busy weather season too.  So hang on…we’ll slowly dry out over the next couple of months.

Chief Meteorologist Mark Nelsen