The Southeast Sucker!

Wednesday, March 9, 2016
12:09 pm

Meteorologists used to have very interesting names for different types of weather. I was introduced to the famed "Pineapple Express" back in elementary school, when it rained 5.02 inches at Sea-Tac during one incredibly rainy 5th grade day. Unfortunately, Pineapple Express seems to have fallen out of favor among meteorologists due to the rise of a potent cannabis strain of the same name, and has been replaced by the much more lifeless "atmospheric river." Indeed, it seems like creativity is being thrown out in favor of bland scientific jargon. How many times have you seen a meteorologist add the word "event" to any type of weather we experience? A "cyclone" has become a "wind event," a flood has become a "rain event," and in my opinion, it's only a matter of time before a "heat wave" becomes a "temperature event."

Thankfully, there are still plenty of meteorologists out there who have given creative yet intuitive names to the different types of weather we experience. We have "Tornado Alley," "snowpocalypse," and the "ozone hole." In our neck of the woods, we have the "rain shadow," the "convergence zone," and, of course, the "Blob." We have cyclogenic bombs and omega blocks, cloud streets and mackerel sky, El Nino and La Nina... the list goes on and on.

But my favorite of all of them? The "Southeast Sucker."

The Great Coastal Gale, the "mother of all Southeast Suckers" - Wolf Read
Image taken 09:00 pm PST, Sun 02 Dec 2007
Credit: University of Washington Online Weather Data Archive

Our current Southeast Sucker
Image taken 02:30 pm PST, Wed 09 Mar 2016
Credit: University of Washington Atmospheric Sciences

A Southeast Sucker is simply a strong windstorm that, due to a fairly far track offshore, creates a pressure gradient over our area that is more east-west oriented than north-south oriented. When this happens, the peak winds in many regions have a strong easterly component. With these storms, the strongest winds are generally found over the coast, the northern interior, and places that are exposed to easterly "gap" winds coming off the Cascades. Enumclaw and North Bend are two places that commonly get strong winds during southeast sucker events, but areas closer to the I-5 corridor can still get breezy if they have ample southeastern exposure.

However, with the exception of the foothills and Northern Interior, most of the Pacific Northwest lowlands west of the Cascades only get moderately breezy from these types of storms. This is because mountain ranges (the Olympics in Washington and the Coast Range in Oregon) help shelter these areas from strong winds and pressure gradients associated with the Sucker.

Here's what the National Weather Service had to say about the Sucker this morning.

"INLAND AREAS OF WRN WA WILL ALSO GET SOME WINDY WEATHER...THIS DEEP LOW IS A CLASSIC SOUTHEASTERLY SUCKER FOR THE INLAND PTN OF WRN WA AND THE WINDY SPOTS WILL BE FROM ADMIRALTY INLET UP THROUGH WHIDBEY AND THE SAN JUANS AND FROM ANACORTES TO BELLINGHAM BAY. FULL GALES CAN BE EXPECTED IN THESE AREAS AND A WIND ADVISORY IS IN EFFECT FOR THE LAND...LOCAL POWER OUTAGES ARE POSSIBLE."

They also produced a handy graphic to outline the impacts of the storm, shown below.

Credit: National Weather Service - Seattle

As you can see, the coast is expected to be the windiest, as it is closest to the storm and receives strong winds coming off the ocean, and it is currently under a high wind warning. The North Interior actually just got bumped up from a wind advisory to a high wind warning, and winds of 30-40 mph with gusts to 60 are expected there. Meanwhile, there are no wind warnings, advisories, or watches anywhere else in Western Washington, as the Olympics shelter many of us from these strong southeast winds. With our storms, the coast and north interior are almost always more windy than the Puget Sound lowlands, but this effect is amplified during these Southeast Sucker events.

Let's take a look at the track and winds of the current storm.

Valid 04:00 pm PST, Wed 09 Mar 2016 - 12hr Fcst

At 4 pm, the storm is between 130 and 135 degrees west longitude and around 45 degrees latitude. There are two centers of low pressure within the general cyclone itself, and this is not conducive to rapid storm development. Nevertheless, the cyclone is pretty deep at ~977 mb and will continue deepening. The coast, particularly the Oregon Coast, is experiencing high winds at this time.

Valid 10:00 pm PST, Wed 09 Mar 2016 - 18hr Fcst

By tonight, the storm has deepened further and is generally heading to the northeast. The two individual low pressure centers are doing a drunken waltz around each other and hindering the storm's development in the process. The front is approaching the coastline, and is bringing very strong winds with it. I would not be surprised if Cape Blanco, an exposed headland on the Southern Oregon Coast, receives gusts well over 100 mph from this storm.

Valid 04:00 am PST, Thu 10 Mar 2016 - 24hr Fcst

The storm continues to deepen early Thursday morning, and a powerful round of high winds approaches the Washington coast. It is now traveling to the NNE.

Valid 10:00 am PST, Thu 10 Mar 2016 - 30hr Fcst

The storm continues its northeastward trajectory before weakening and slipping to the south. Through it all, the coast has gotten absolutely pounded, the North Interior has taken a good beating, and most inland areas have escaped relatively unscathed. However, they will be wet, with some of the volcanic peaks such as Mt. Rainier and Mt. St. Helens possibly picking up as much as 10 inches of rain in 24 hours!

Valid 04:00 am PST, Thu 10 Mar 2016 - 24 Fcst

One more picture, and then I'll peace for now. This graphic shows the surface winds just like the graphics above, but does so at much higher resolution. If you look carefully, you can really see the easterly component to the winds north of the dramatic warm front near Grays Harbor.

Additionally, you can see that there are strong winds at the exit regions of gaps, with breezy conditions near Enumclaw, Randle, Gold Bar, and many other locations in the Cascade foothills. The northwestern tip of the Olympic Peninsula is particularly windy, with sustained winds of 45 knots near Tatooosh Island. I'm looking forward to reviewing some of the wind velocities from Tatoosh Island after this storm has passed, as they could be quite impressive.

Valid 04:00 pm PST, Wed 09 Mar 2016 - 12hr Fcst

Even though it will be mild, snow levels won't be sky high. It's snowing at Snoqualmie Pass right now. Let's hope it stays that way!

Peace for now,

Charlie