Brief return of summerlike warmth next 2 days; looking back on Tuesday’s wavy clouds
Wednesday’s Weather Journal column: Fogs-in-August lore difficult to see amid facts
There is nothing new under the sun, it is written in Ecclesiastes. There is nothing new under the sun when it comes to cloud types — the wavy clouds that invaded the skies of the Roanoke and New River valleys late Tuesday afternoon ahead of an unexpected line of rain showers have been in our skies before, many times. But they were of a type that has not yet drawn its own classification name, and some weather scientists and enthusiasts are pushing for the name “undulatus asperatus” to be applied to the clouds. The clouds are generally caused by warm, moist air overriding cool, dry air, and then being undulated and sculpted by wavy wind flow aloft. Such wave-like wind flow often occurs over mountain ranges, so we should expect to see these clouds from time to time in our skies when the conditions are right. They have been considered a subset of altocumulus, altostratus or stratocumulus in the past, or even somewhat related to mammatus clouds, but if the cloud’s promoters are successful, undulatus asperatus may become the first new cloud type recognized since 1951. So you didn’t see a new kind of cloud type on Tuesday, but may have seen a cloud worthy of its own new type. (Inset photo taken by Miranda Beck in Salem.)
Summer is likely to make a brief encore on Wednesday, and to a lesser extent, on Thursday. We are on the warm side of low pressure and a slow-moving cold front in the Ohio Valley. Tuesday’s surprise showers were the first manifestation of this switch, as some Gulf of Mexico moisture overran the cool, dry air that has dominated our weather for days. With ample sunshine that is expected Wednesday, highs could go well into the 80s — a random 90-degree reading in Southside may not be out of the question. Thursday could be almost as warm, but as the week transpires, we’ll be more affected by the sluggish front and disturbances moving along it. It will be difficult to time rounds of showers and some storms through the weekend, but most days from Thursday into early next week are likely to have some chance of showers. Hopefully the timing will be a bit more clear as the new weather setup unfolds.
September 26, 2012 - 12:50 AM
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Kevin, not sure how to send pictures to you. I took 2 pictures yesterday at the old “Harris Teeter” Kroger on Brambleton of the “wavy” clouds. When I went in around 3pm to get groceries, it was cloudy, but nothing unusal. I came out around 4:10 and the sky was, for lack of a better term, wicked looking. Everyone around me just stopped to stare at the clouds. So obviously I had to take a quick picture with my phone LOL. I’ve never seen anything like it before.
Already 80 up here and only 1pm. Dry and hot is best to describe this weather, oh well makes for good hard greens. Greens were running close to 12 on the stimpmeter this morning! Ready for some rain, haven’t received any since last Tuesday. Kevin, when is the next chance for good measurable rain?
I saw those clouds as I was leaving work and thought “Snow clouds in September??”. They were awesome looking!
Jared I’d say late tonight through Friday is the best shot of rain where you’re at. But it’s likely to be kind of streaky and patchy.
Gloaming Girl: They were similar to the mid-level clouds that begin moving in ahead of a winter storm. Maybe a little more turbulent looking. Similar principle though — mid-level moisture overrunning cooler, drier air at the surface.
Very good article on fogs and snows, Kevin. A+ Guess we will have to wait and see how things turn out this winter.
Good article. For your next one, visit the wooly worm debate. They have all been blonde to light brown so far here on da Knob.
Check out this incredibly tightly wrapped storm system in the Gulf of Alaska.
https://www.facebook.com/photo.php?pid=1027454&l=03b4aa5901&id=162655917140206
Being the inquisitive one I am, and looking at that Alaskan satellite, assuming it’s a 950 mb low, is there a general formula to determine wind speed based on pressure alone? And would that same formula apply to tropical systems?
For the few that might not have seen the Replacement Weather Guy.
http://sports.yahoo.com/blogs/nfl-shutdown-corner/video-green-bay-tv-station-uses-replacement-weather-222926781–nfl.html
Hey, Kevin, what does the weather map of the USA look like right now? In other words, is there a trough in the west and a ridge in the East? Or no particular trough/ridge pattern?
Prudhoe Bay and Deadhorse..
What Kevin said…in print.
..changes in latitide..changes in attitiude..
(Sorry Jimmy)
AKZ203-270530-
CENTRAL BEAUFORT SEA COAST-
INCLUDING…NUIQSUT…PRUDHOE BAY…ALPINE…DEADHORSE…KUPARUK
820 AM AKDT WED SEP 26 2012
UPDATED TODAY
.TODAY…CLOUDY WITH SCATTERED RAIN AND SNOW SHOWERS. AREAS OF FOG
AND DRIZZLE. HIGHS IN THE UPPER 30S. NORTHWEST WINDS TO 10 MPH.
.TONIGHT…MOSTLY CLOUDY. A CHANCE OF SNOW. AREAS OF FOG. LOWS
IN THE UPPER 20S. WEST WINDS TO 10 MPH.
.THURSDAY…CLOUDY. SNOW LIKELY. AREAS OF FOG. SNOW ACCUMULATION
OF 1 TO 2 INCHES. HIGHS IN THE MID 30S. WEST WINDS 10 TO 20 MPH.
.THURSDAY NIGHT…CLOUDY. A CHANCE OF SNOW. LOWS IN THE MID TO
UPPER 20S. WEST WINDS 10 TO 20 MPH.
.FRIDAY…CLOUDY. A CHANCE OF SNOW. HIGHS IN THE LOWER TO MID
30S. WEST WINDS 5 TO 15 MPH.
.FRIDAY NIGHT…CLOUDY. LOWS IN THE MID 20S.
.SATURDAY…CLOUDY. A CHANCE OF SNOW. HIGHS AROUND 30.
.SATURDAY NIGHT…MOSTLY CLOUDY. A CHANCE OF SNOW. LOWS IN THE
MID 20S.
.SUNDAY THROUGH MONDAY NIGHT…MOSTLY CLOUDY. HIGHS AROUND 30.
LOWS IN THE LOWER TO MID 20S.
.TUESDAY…MOSTLY CLOUDY. HIGHS IN THE MID 30S.
&&
TEMPERATURE / PRECIPITATION
DEADHORSE 38 28 35 / 30 30 60
According to Brent Watts of “7,” the high/low combo at ROA Regional Airport today was 84/64. Nice average day here ….. for late AUGUST, not late September. If 84 was the high, the bullet just barely missed me.
Doug: Across the southern half of the U.S. the jet pattern has pretty much flattened out into a west-to-east zonal flow. That’s why these fronts are hanging up instead of pushing through. There is a decent trough dipping into New England, and a weaker one in the Northern Plains. The more amplified pattern is Alaska/West Coast, with the super-strong low pumping up the West Coast high. We’ll eventually get some impact from that — like whipping a garden hose, that will ripple downstream, probably into some amplified highs and lows in the next couple of weeks.
Matt: Low is 956 mb projected by models to dip to 948 mb. Because the wind speed would depend on the gradient between high and low pressure, not just on how low the pressure is in the center of a storm, I’m not sure there would be a really easy millibars to mph formula.
Northern Pacific storms can be as strong as a Category 1 to Category 3 hurricane, with a much broader wind field.
Kevin…
I scanned the observations over all of Alaska..
I didnt see many over 30kts…but a few stations
had gusts into the mid and upper 30-s..
I did see one flood warning from what appeared to be
glacial movement of sorts.
Ill go dig that back out and post it.
It was a Glacial Lake outburst..
AKZ141-270000-
COPPER RIVER BASIN-
INCLUDING…GLENNALLEN…EUREKA…MCCARTHY…PAXSON…SLANA
150 PM AKDT WED SEP 26 2012
…FLOOD ADVISORY IN EFFECT UNTIL 600 AM AKDT SATURDAY FOR A GLACIAL
LAKE OUTBURST NEAR TAZLINA LAKE AND THE TAZLINA RIVER NEAR
GLENNALLEN…
.TODAY…PARTLY SUNNY. HIGHS IN THE LOWER 50S EXCEPT IN THE 40S
THROUGH THE PASSES. SOUTHEAST WIND 10 TO 20 MPH.
.TONIGHT…CLOUDY WITH A CHANCE OF RAIN. LOWS IN THE 30S. NORTH
TO EAST WIND TO 15 MPH.
.THURSDAY…MOSTLY CLOUDY. A CHANCE OF SHOWERS ALONG THE MOUNTAINS.
HIGHS IN THE LOWER 50S EXCEPT IN THE 40S THROUGH THE PASSES.
SOUTHEAST WIND 10 TO 25 MPH.
WD: I would need the help of a biologist before tackling woolly worms or the acorn mast issue. Fogs/snows was simple for a weather geek, just looking up weather observations.
Kevin…
I wouldnt be a bit surprised if it
were Scottish or Irish in origin..
Their story telling and bent favoring exaggeration
(I KNOW PLENTY ABOUT THIS) sure seems plausable to me.
http://homepages.abdn.ac.uk/wpe001/meteo/lore.pdf
Some of us have heard similar to a bit of what is here..
Some good wisdom in the link Joe posted about never basing a prediction on a single sign. It was talking about folklore, but it applies to modern computer models, surface observations, etc. No weather event has a singular cause, so basing a forecast on a single signal is foolhardy.
My computer will not let me email you Kevin, so I tagged you on twitter.
I’ll post your pic over in the new blog entry I just posted.
Kevin, I was mostly curious to see if the western states, especially Wash and OR, were colder than normal. I just checked their current conditions and forecasts, and for today and tomorrow they are just about at normal. But going cooler than normal during this weekend. If their upcoming cool weekend is partially a result of that powerful storm just south of AK, then that is a first example of what the 3-month TWC forecast for OCT-DEC predicted. Cold waters in the northern Pacific, trough in the northwestern USA, and a ridge in the East.
I think that pattern may take hold later in October and November. But not too much in the next couple of weeks. Looks like at least a brief resurgence of the cool pattern we’ve been experiencing.