Category Archives: Story

Strong spring system looming this week

It’s not often that the entire country will get to enjoy the forces of the same system, but that’s what we are looking at right now. As of this moment, the feature is a weak, cold air system bringing snow to the northern Rockies and Pacific Northwest. Radar imagery is less than stellar in this part of the world, so let’s instead take a look the advisories that are out from the Weather Service for the snow.

The system at this moment is fairly disorganized aloft and at the surface. It will get some structural definition as the surface trough dips past the Rockies tomorrow night. We’ll see a closed low developing, which will initiate the drawing of warm air north and cold air south. There is a bit of disorganized warm advection leading to some scattered showers north of the Gulf of Mexico tomorrow night. 

The upper level trough will lurk west of the Rockies at this point, essentially handicapping the ability for the feature to take on much moisture initially. Things will change very quickly on Tuesday and especially Wednesday, as the storm moves eastward. Here is what the model has in place on Wednesday, with the strong system tapping into all the available moisture.

As you can tell, the feature will have deepened dramatically from tomorrow evening by mid day Wednesday, and started bringing about some serious precipitation to a good deal of the eastern third of the country. You might note that I haven’t been talking about snow since this storm breached the Rockies. That is because we won’t remember this as a snow storm. Note those red isohypses running all the way up to the Canadian Maritimes. This will be a severe weather event. The SPC is looking at Tuesday and Wednesday for severe weather.

There is a bit of a difference in model guidance at this point. The NAM foresees a secondary low developing in the Lower Ohio Valley, at the base of the upper level trough, before continuing northeast towards New England. This would likely shift the onus of severe weather a shade to the north, and prolong the threat for severe weather later into the night and day.

Stay tuned, as this will certainly be the top weather story this week.

Mea Culpa

A couple of days ago, I wrote about the looming storm, getting ready to pound the Twin Cities. The storm did drop a foot of snow on some locations, but the storm went a little bit further south than it was supposed to. By a little bit, I specifically mean the Twin Cities metro, by and large, did not receive a single flake. Go back and look at the imagery from a few days ago and see how confident meteorologists across the region were that Minneapolis would receive not just some snow, but at least 8 inches of snow.

So it didn’t go well. The Weather Service, to their credit, adapted their forecast to account for the changes in model guidance.  Meteorologists have a thick skin to criticisms, because we understand that only the final product is seen by the public, and not the hard work that goes into it. That’s why the NWS Twin Cities was able to put together this well considered statement regarding the shift in forecast. It’s not so much an apology as an explanation.

We’ll see how well received it actually is.

Twin Cities poised to get clobbered with snow

I haven’t seen this product anywhere, aside for the National Weather Service office in Chanhassen, Minnesota. This might be because there is no Weather Service office I am so personally invested in as my local office. They have a winter weather page that they haven’t been able to break out very often this year, but with a deep, moisture rich system headed towards the Twin Cities, now is the time to explore all this page has to offer.

First a little background for the pending storm. The heaviest snow storms generally come from the south, where they can fetch the necessary moisture, deepen as the round their way out of a deep trough, and pull cold air towards it as the system moves to the north. The system, arriving tomorrow afternoon, will continue through the day Friday, and will bring a bunch of snow from Sioux City, Iowa to the Twin Cities. There is currently a blizzard watch from Sioux Land in South Dakota and Iowa to southwestern Minnesota, just outside the Twin Cities metro. Now, if only there was a more precise way to estimate how much snow that part of the world will get.

Check out these informative images from NWS Twin Cities at http://www.weather.gov/mpx/winter I don’t even need a caption for them because they are that comprehensive and informative! Check out the actual site, for a percentage break down of the chance for specific amounts of snow at specific locations.

 

More video from southern California

That, of course, is a fire truck, falling off of I-15 in Southern California. There have been reports, video and imagery of sinkholes in SoCal thanks to all the rain, most notably one in Studio City that has swallowed cars. This is the most dramatic video of collapsing soil. The fire truck was responding to a semi that had also fallen off the side of the road.

Flooding rains continue to pound California

We all heard about Oroville Dam’s flooding concerns last week. An auxiliary spillway draining Lake Oroville was eroding after a very wet beginning to 2017. Fortunately, the spillway has held, and flooding has not yet occurred in Oroville.

Unfortunately, street flooding has been a concern up and down the West Coast, with southern California catching it in the teeth today. Two people have been killed as a result of the torrential rains and blustery conditions, with incredible scenes coming from the Los Angeles area. Take a look at this article from NBC with images from the storm.

The bad news is, the torrent isn’t going to stop any time soon. Take a look at these images over the course of the next week and a half. There are three separate storms poised to bring more heavy precipitation to the west coast in the next 10 days or so.



Those are from three distinct features, coming tomorrow, Monday and Wednesday. The activity later in the week will put additional strain on the Oroville Dam and its spillways. The drought in California is quickly being alleviated, but now, California needs a break.

A quick round of severe weather grazes the Gulf Coast

More dramatic video from today's possible tornado. This is home security video from Allsbrook in Horry County. Watch the shed in the background!

Posted by WMBF First Alert Weather on Wednesday, February 15, 2017

There was a cutoff bit of energy that looked almost spring like in profile, thanks to the tight turning and lack of strong flow through the trough that glided from the Plains to the Southeast and off shore through the early bit of this week.

Yesterday, there were tornadoes in the Houston area, causing damage to the region, with the city of Van Vleck receiving the brunt of the damage. The storms were mostly offshore overnight, but earlier today, they reorganized and slammed south Georgia and South Carolina. The above video is from a suspected tornado that struck Horry County, near Conway, South Carolina.

This follows a busy start to the year in the Gulf Coast. A handful of tornadoes hit the New Orleans area earlier this month, and south Georgia was battered in January. There is  a reprieve coming, at least for a few days in the Southeastern US. Attention now turns to the West Coast, were flooding concerns continue.

Deep trough indicates what is to come

It’s not a terribly active pattern right now, which is a reflection of the broad upper level wave pattern. In this case, there is a trough, generating a low along the Labrador Coast. There are two things to note. It’s a very long waved trough, meaning it will move somewhat slowly, and secondly, the flow through the jet is very strong.

Strong flow through a jet streak is indicative of a dramatic temperature gradient, meaning temperatures on the south side are significanty warmer than those on the north. So, with a strong flow through a jet, with the pattern being only marginally progressive, we can infer what the temperature map might look like.

This jet won’t be getting weaker, and the temperature trends won’t be changing, at least not until the end of next week!

Drought Buster

It’s been well-documented and publicized just how bad California’s drought had gotten over the last few years. Picture after picture of dry riverbeds, parched lakes, reservoirs at a tiny fraction of their capacity. One year ago, the ENTIRE state was in at least some stage of drought, while over 60% of CA was in one of the top 2 tiers of drought level. El Nino last winter was supposed to take care of some of that… but sadly most of the activity was diverted over the Pacific Northwest, leaving CA continuing to wallow in drought despair.

…but despair no more! The constant parade of storms over the last month has done wonders for the state’s rivers, lakes, reservoirs, and snowpack in the Sierra Nevada. Most of the snowpack levels are well over 150% of normal, which will do wonders in the Spring. Long Beach set a record for the rainiest day EVER on record (since 1959) last week. Also, all this rain/snow in a short amount of time has lead to flooding in parts around the state, as one of my friends who lives near Stockton found out the hard way. The state gets a bit of a reprieve for the next few days as a ridge of high pressure as parked over the Western US, letting some of those flooded areas dry out. This has been a very encouraging month, however, to fixing the state’s drought problem and getting the state back to normal. Here is a side by side comparison of the drought levels from 1 year ago vs today. Look at that improvement!

Massive severe weather outbreak clobbers the southeast

Over the past 24 hours, the southeastern US has been pummeled by a virulent area of low pressure that tapped into both the warmth and moisture of the southeast and the still wintry conditions found in the middle of the country. The tight circulation associated with the low brought tornadoes from Arkansas to Florida. In between, particularly in southern Mississippi and Georgia, they were tragic.

Tornadoes and other strong wind events have killed at least 18 people, most of them in Georgia, particularly near Valdosta. The first deadly tornado of the sequence went through the Hattiesburg area. A recent tweet from the Jackson NWS office highlights the pertinent information from this storm, in which 4 lost their lives.

The hardest hit area was Petal, which is just across the river from Hattiesburg.

In Georgia, the town of Adel sustained a great deal of damage, where 7 people were killed. The initiation of this activity today even looked ominous. I captured a radar signature from early this afternoon.

Thos isolated cells running west to east were all rotating, and would ultimately drop the tornado that would be fatal in Adel. The rest of the line would continue to produce discrete supercells throughout the rest of the day, verifying the SPC’s outlook, putting forth a “high risk” for severe weather.  Florida had never been placed in a high risk before today.

Another startling feature of this storm was just how far to the south supercells appeared. This is obviously an anecdote, but I can’t recall ever seeing supercells as far south as Orlando before. This is because the change in airmass is usually not as severe, thanks to the modifying impact of the surrounding ocean. Not today.  Storms are still raging across the southern portion of the state, and there have been severe reports as far down the Gulf Coast as Bradenton, where there was mobile home damage.

There remains a tornado watch, including Miami, Fort Lauderdale, West Palm Beach and Key West as storms continue across the tip of the peninsula. Severe warnings are presently out for West Palm, and winds of 50mph have already been reported in Fort Lauderdale, though those reports haven’t officially been logged by the SPC. Fortunately, this line of storms is the end of it, at least for a while. We do still have the entire spring to look forward to.

(Just before I pressed publish, the severe storms have lead to a warning for Key West, which is another thing I have never seen before)