This late night look at the iwind gusts across the country should give everyone a good hint as to why the kids are up, worried about monsters outside. The gusty winds are causing limbs to creak and branches to scratch windows from the Great Lakes and mid-Atlantic to the Gulf of Meico, and in the northern High Plains as well, all in the wake of a cold front that has just crawled over the Appalachians, and will push off the coast over night, and ahead of the next system from the Pacific Northwest.
This time of year, systems are outsized with sharper changes in air mass ahead of and behind systems. As a result, even when we are between systems, the autumn can be one of the windiest times of the year.
I think most people would agree that the 2017 hurricane season is one best left for the scrapbook, and hopefully revisited infrequently. It was brutal, expensive and painful. Still, there is a great deal that can be learned from the season, both in terms of forecasting, as well as in terms of adaptation of coastal areas, so they might withstand stronger storms in a changing world.
Well, the first thing we need to do is increase our appetite for learning. One way to do that is to enjoy attractive videos of the season. Here is NASA’s version:
This animation displays an aerosol analysis of the time from August through September, showing the course of a few different types of particulates in the atmosphere. In it, you can see Saharan dust, smoke from the northern Rockies and evaporated sea salt. You can see the contortions within those plumes of dust as the storms spiral through the Atlantic.
Even if there wasn’t much to learn from this video, this attractive video at least gets us to look at the 2017 season again, and that’s the first step in teaching what we can about it to the broader public.
If you are waking up this morning in New York or New England and are reading this today, you likely already know this: it’s cold out there! Here is a look at the forecast morning lows across the region:
The only thing keeping Boston, New York and Philadelphia in the 20s is proximity to the coast and the urban heat island effect. Inland, temperatures are barely in double digits in central New York or Pennsylvania.
If this seems cold to you, it’s not just because this is the first bout of cold weather for the season, but it’s also the earliest it’s ever been this cold in places like New York. It’s going to be a record low, and the lowest temperature ever seen this early in the year in New York City! If you aren’t a fan of the cold, then I grant you the right to complain about this outbreak of cold. No, it isn’t supposed to be this cold this time of year!
The month of October was a very busy month on the forecasting front, with 17 forecasts verified in total, which might just be a record. I think that this is, therefore, a good accounting for the meteorological skill of the top forecasters in the country, particularly given that October is a month of transition, and there were the dramatic fires out west, and an unseasonably cool shot in the Great Lakes, and a strong storm that screamed up the coast late in the month. OK, enough beating around the bush… Your October forecaster of the month is Victoria-Weather!
Tropical Storm Philippe technically drifted to extinction over the northern Bahamas, but a cold front moving through New England tapped some of its remnant energy after they began merging in the Mid-Atlantic. Eventually the system exploded, thanks to good jet dynamics, and New England caught the storm right in the chin.
The system was in such a favorable environment as it moved north, it is said to have “bombed out” in the parlance of meteorologists, which is to say the central pressure of the low dropped a millibar an hour over the course of a 24 hour period. It didn’t sustain that growth, but the rapid development was still quite significant, and this particular dynamism helped to feed the particularly nasty conditions that were seen, especially in southeastern parts of New England.
Over a million are without power in New England a day later, and the rapid intensification of the storm led to some incredible wind gusts, including some hurricane strength winds of 93mph on Cape Cod. That’s stronger than any of the winds Sandy put forth as she charged through the mid-Atlantic!
One fundamental and important difference was that this storm organized nearly on top of southeastern New England, so the storm surge didn’t have enough room to really become damaging. The half a foot of rain some places received caused problems enough, but those issues were distributed inland, and coastal areas weren’t obliterated.
Ultimately, this storm won’t be remembered on the scale of other late October storms like Sandy or Irene, but it was definitely a harsh end to the month, and a powerful reminder of just what the Gulf Stream has to offer this time of year.
October and November is when there are typical large swings in weather patterns throughout the US, as the jet stream begins to buckle back down to the south and pushes of colder Canadian air begin to penetrate the Northern US. Sometimes these patterns can stir up bouts of late-season severe weather, since the contrast between the still warm and humid Gulf region and cold air from the north can be quite sharp at times. Saturday looks to be one of those days as a large cold front is pushing through the Plains tonight and by Saturday evening will be found from MN down to Central OK/TX Panhandle, kicking up showers and thunderstorms along its’ length. An embedded area of low pressure found along the front in KS/OK looks to be a trigger for more potent thunderstorms, as the SPC has put out an Enhanced Risk for much of Central OK. Some supercell thunderstorms are expected to pop off over western OK but then evolve into more of a squall line as storms push eastward into the overnight hours. It may be late-October, but Mother Nature isn’t quite done with severe weather outbreaks quite yet!
I think we can all say honestly that of all the Atlantic Islands to be battered by a tropical feature this year, Ireland was not near the top of our list. Alas, Ophelia is a nasty extratropical cyclone, battering the British Isles today in a strange turn in an already unusual tropical season.
Ophelia is the easternmost hurricane in recorded history, and this was before she became post tropical and clipped the western counties of Ireland, killing three and knocking out power to hundreds of thousands of people. She is continuing towards Scotland today, and will impact Scandinavia later in the week.
Getting nasty weather from the Caribbean or tropical Atlantic isn’t that unusual for Ireland, however. Consider that in the southwestern part of the island, there are actually palm trees, transported as seeds from the Caribbean by those same currents that guided Ophelia and many other storms, albeit non-tropical to the British Isles in the past.
We tend to forget about these tropical features after they have left North America, but a common graveyard for tropical systems from the western Atlantic is actually Iceland and the North Sea. They batter the southwestern part of the island, keeping it the dismal but somewhat verdant island that it is
Typically, storms follow the Gulfstream off the coast of North America before teetering off towards the North Sea. Storms that the rest of continental Europe sees tend to drift through the Atlantic before veering back into the continent, if they are indeed of oceanic provenance. For a tropical system to be traceable to a hurricane, however, is very unusual because the central Atlantic is quite foreboding to those storms, thanks to the broad and chilly Atlantic.
Indeed, the typical route is for such storms to go north, up and over the Sargasso Sea, following the warmer currents towards Iceland. Ireland, though it is on a parallel latitude with Labrador is, unintuitively, an unusual place to receive a post tropical storm because of how far south it is. They get their share of nasty weather in Ireland, and despite some fatalities and power outages, the Emerald Isle should be able to weather Ophelia as well as one could hope.
At this late hour, the NWS radar is full of ground clutter, so forgive me for pulling the SPC version. I want you to be able to appreciate the two major factors t work here. In the mid-Atlantic and eastern Great Lakes, there is a big mass of showers. This is partially thanks to a weakening cold front moving out of the area, but mostly thanks to the remnants of Nate, a tropical storm.
Meanwhile, take note of that band of showers from Pierre, South Dakota to Fort Collins, Colorado, and beyond, towards Craig. That is not rain. Here is a look at Cheyenne, Wyoming from the NWS:
— NWS Boulder (@NWSBoulder) October 9, 2017
Yikes. That cold front will move southeastward, and while the snow is really only a concern in the high Plains and central Rockies, there will be some cold temperatures making their fiirst real incursion into the continental US. Check out all the purple, pink and blue on this map, indicative of cold or wintry weather on the way.
Winter is almost here, in spirit anyways. Of course, as Brian Brettschneider notes, we’ve also just had our first 0 reading in Alaska.
— Brian Brettschneider (@Climatologist49) October 9, 2017
Nate ended up reaching that Category 1 hurricane status before he reached the United States. Nate made an initial landfall around the Mississippi Delta before he slipped further northeast towards Mississippi, making a secondary landfall near Biloxi. Winds are around 80-90mph maximum sustained strength as he continues to move inland.
The most significant concern to date has been a 6-8 foot storm surge from Biloxi over to Mobile Bay, east of the center of low pressure. You can see some pictures of Biloxi below.
— Brian Emfinger (@brianemfinger) October 8, 2017
Fortunately, the storm is moving quickly, and by the time people get going Sunday morning, the system will move away from the coast and these flood waters will recede. Still, pay attention to the feature as he continues his northward progression through the day tomorrow, as there will be sudden heavy rain, and a continued threat for tornadoes up until the southern Appalachians.