This blog discusses current weather, weather prediction, climate issues, and current events
This summer, wildfire activity east of the Cascades has been above normal. Several media outlets and activist websites are claiming that this year's low snowpack is a major cause of the wildfires (see example below). Poor mountain snowpack and early melt-offs have translated to low reserves, drying out grasses, trees, and shrubs that easily ignite and spread wildfires. The facts are clear: such…
Good news for those of you who dislike heatwaves: There are none forecast over the Pacific Northwest for the next 10 days. Importantly, we are running out of time to experience a serious heatwave in our region. First, let's define what is meant by a heatwave. According to the WMO (World Meteorological Organization), a heatwave occurs when there are more than five consecutive days during which the…
This year, wildfire acreage in California has been well below average and is being eclipsed by the lightning-initiated wildfires in the Pacific Northwest. The nearly fire-free California situation is evident satelite/ fire image from yesterday (active fires shown by the orange dots). Lots in Washington and Oregon, very little in California. In fact, according to official CALFIRE statistics (shown…
On July 15/16, a massive lightning storm initiated several major wildfires east of the Cascade crest. As shown below, this was one of the most extreme lightning events in Northwest history. This story has escaped the notice of the media. Furthermore, several media outlets (including KING-5 news and the NY Times) and podcasters/Youtube channels have claimed that Northwest lightning has increased…
As expected, air quality is rapidly improving west of the Cascades, with the transition complete by tomorrow morning. You can see the changes in the west in the visible satellite imagery at 11 AM yesterday (top) and today (bottom) The smoke plumes are now directed to the east, as the winds have reversed to westerly (from the west). Low marine clouds have pushed up the coast and invaded coastal…
As predicted, the winds aloft have turned easterly (from the east), resulting in smoke from eastern Washington moving aloft over western Washington. This is actually good news for eastern Washington, as it leads to reduced wildfire activity and eastward fire movement. This situation is only temporary, and later this week the situation will reverse, again pushing strong westerly winds into eastern…
One of the most interesting aspects of the current smoke/fire event is that it is occurring during a cold wave. Over the past few days, temperatures in eastern Washington have been well below normal. Not a heat wave associated with global warming. A cold wave with strong winds. Don't believe me? Below are the daily low surface temperatures yesterday and today (only showing values of 40F and…
As feared, the great enhancement of cool, westerly winds caused a large increase in eastern Washington wildfires, with the Little Giant Fire expanding to Lake Chelan. The change in visible satellite imagery yesterday shows the major changes Early in the day Saturday, you can see the smoke from a few fires in eastern Washington, with the Little Giant Fire possessing only a modest amount of smoke.…
Rain is coming to western Washington and the Cascades during the climatologically driest time of the year. But there is an accompanying risk that needs to be mentioned . A severe enough risk that at least one local power company (Chelan PUD) may de-energize its lines: A winter-looking system is off our coast, including an impressive cold front (indicated by a red arrow) and a low center at the…
With the recent grass/range fires in Eastern Washington, there is some interest in whether conditions there have gotten drier or warmer. How unusual have precipitation and temperature been this year? Let's find out! I will start with the NOAA Climate Division dataset, which is derived from multiple climate observation locations in each division (the climate division map for Washington State is…
During the last few weeks, a series of wildfires have occurred over the region. Today's satellite imagery shows where the fires were burning (orange dots), with smoke plumes quite evident. Most of these fires began in grass/range vegetation. In mid-June, there were a few grass/range fires in the Columbia Basin (see image below). There has been drumbeat in the media that the wildfires were the…
On Thursday around 5:15 PM, a Kenmore Air float plane crashed on the south side of Sucia Island in the San Juans. An image from the final seconds (shown below) does not suggest particularly strong winds at the surface, nor any precipitation. The weather radar at the time of the incident shows a convective/thunderstorm line just to the south, but with the crash location (indicated by the red arrow)…
Sometimes the weather gets stuck in a totally benign pattern, with little threat of heatwaves, wildfire explosions, heavy rain, or anything else of note. During the next week or so, we will be stuck in such a boring pattern, with great benefits for our region. To demonstrate this benign situation, consider the forecast upper-level (500 hPa pressure, about 18,000 t) for Sunday morning. A ridge of…
9:30 Update The showers and thunderstorms are here (see radar image). And cooler air is moving in from off the ocean. Lightning at 8:10 PM: ________________________________________________________________________________ A line of thunderstorms is now moving up western Oregon at this time and is heading into western Washington. A little after 2 PM, the thunderstorms were evident in the infrared…
We are now approaching the driest time of the year, and ironically, it is going to rain that day. Temperatures will cool. An important contributor will be a weakening tropical cyclone (Elida). Below is the path of that storm from the National Hurricane Center: And a recent infrared satellite image shows the moist storm off the northern California coast. But where will the tropical moisture go? You…
During the next few days, temperatures will surge upwards west of the Cascades into the low 90s, but a significant smoke intrusion is NOT expected in the west. This is in contrast to highly deceptive (and incorrect) media reports, such as in the Seattle Times (see below). In fact, a lot of media outlets are providing such inaccurate information (such as Public Radio Station KUOW: Currently,…
As expected, the massive lightning event this week led to the ignition of several wildfires. But our region lucked out: few fires were started on the eastern slopes of the Cascades within forested areas. This is because we are in the early season, which means less time for drying in the slow-to-dry forested areas, and because of the distribution of lightning (relatively little lightning on the…
One of the greatest Northwest lightning outbreaks in recent memory occurred today, with well over 5000 lightning strokes over the region. Below are the strokes over the past 24 h: very impressive. There were three major thunderstorm paths...one down the lowlands of western Washington, one along the coast, and a broad band in eastern Oregon and Washington. Importantly, there were very few lightning…
For most summers, during July or August there is an intrusion of "monsoon" moisture from the southwest into our region, resulting in showers and thunderstorms...and this year will be no different. Such thunderstorms can be both good and bad. Good at providing needed rain and lessening fire risk, but bad if lightning starts fires. The predicted totals through Friday morning (seen below) range from…
If you viewed the skies around sunrise and sunset during the last day, it was evident that a massive cloud of smoke had moved in overhead. For example, here is a northwest view from the Seattle PanoCam just before sunrise this morning. Stunning. Lots of smoke in the sky. And if you needed more evidence that our sky was full of smoke, below is the visible satellite image at 6:52 AM this morning…
If you asked Google AI where the best weather in the U.S. will be, the answer will warm your heart: Seattle gets called out with "perfect weather conditions". As a trained meteorologist, I concur. The forecast high-temperature map for Sunday across the U.S. shows only one urban area in the upper 60s to low 70s: western Washington. Even eastern Washington is reasonable. You dislike humid conditions…
Late June or early July is the traditional start time for the North American (or Southwest) Monsoon, during which moisture streams northward from Mexico into the southwestern U.S., bringing substantial showers to Arizona, New Mexico, Nevada, and sometimes Oregon, Idaho, and eastern Washington. See the schematic below. Such monsoons are often associated with an area of high pressure over Colorado…
One of the reasons Northwest weather is so temperate in summer is the cool coastal waters off our coast. And this year, we start the summer with surface waters cooler than normal. This is illustrated by the sea surface temperature anomalies (differences) from normal (below), with blue indicating cooler than normal water. Below is a map of sea surface temperatures off the U.S. West Coast (°C). The…
The Chelan Hills fire, reported to have been started by some irresponsible fireworks Saturday morning, has now spread to over 10,000 acres (see map below). A high-resolution visible satellite image this morning shows the burnt area (dark color), and the satellite imagery shows some still-active fires (red dots). Smoke from another (smaller) fire is apparent to the southwest. The fire started in…
Walking my dog yesterday, I ran into a neighbor who asked whether July 4th temperatures in our area had changed much under global warming. I promised to run the numbers... and here are the results. Be prepared to be surprised 😀. Starting at Olympia, on the western side of the state, there is almost no trend in July 4 daily average temperatures since the 1940s! (The purple line is the linear…