Crazy Weather — Last Minute Changes

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The Palm Springs area is known for it’s beautiful weather, especially now during ‘the season.’ For most, today was no exception. For some it was nuts!

I planned on showing a telescopic image of last night’s asteroid fly-by. It’s cool show-and-tell. I got to do that at five, but it was quickly pushed off my agenda.

My forecast yesterday called for moderate to strong winds this afternoon. By 4:30 police had closed Gene Autry Trail in Palm Springs because of reduced visibility in blowing sand! I quickly worked up a graphic showing the gusts tonight.

As we went to air (and the road reopened) I got a photo of what looked like a funnel cloud. I hurriedly pushed that into my TriCaster and aired it a few minutes later.

It was probably a landspout. Conventional tornadoes come from mature storm cells. Landspouts are weak tornadoes that form early as storms are building.

This evening I got the video you see at the bottom of this entry. It’s the landspout near Desert Center (population around 150), a rural community surrounded by sandy wilderness. I showed it briefly at 9:00 and will feature it again at 11:00.

The landspout was unexpected, unforecast and unseen by Doppler radar! Luckily, It did no harm. It made for great TV.

A Definite Maybe

rtwrfdomainsSince last Wednesday I’ve been talking about the chance of the Palm Springs area getting a few sprinkles this Thursday. In most places caring about an iffy forecast for a tiny event so far in advance would be a non-starter. Not so in the desert where long time residents look forward to our few cloudy days!

So, here we are Monday. This is the sixth day since rain was first mentioned. I’m barely closer to knowing than I was then!

First, an admission. Without supercomputers no one could attempt a seven or eight day forecast. The atmosphere’s just too complex. But computer’s have shortcomings. I use the GFS model this far out.

The entire globe is covered by the GFS at a base horizontal resolution of 18 miles (28 kilometers) between grid points, which is used by the operational forecasters who predict weather out to 16 days in the future. Horizontal resolution drops to 44 miles (70 kilometers) between grid point for forecasts between one week and two weeks.

One point every 18 miles! At that resolution mountains disappear. Everything becomes a coarse approximation.

Later today Thursday will be seen in the much higher resolution CANSAC (California and Nevada Smoke and Air Committee) WRF model. CANSAC’s WRF only sees out 72 hours, but with 2km (1.2 mile) resolution.

For the geekiest reading, here’s the hardware CANSAC uses to run the WRF.

The CANSAC WRF real-time forecast system is operated on an SGI® ICE 8200 high-performance computer. Specifications are:

256 cores (Intel Xeon X5570)
384 GB RAM memory
20 TB disk space.

In the interim lots of human expertise is needed. The mountains west of the Coachella Valley are critically important. The models might not resolve them well, but I have to. They are a major reason we see less than six inches of rain in an average year (just over two inches since this year’s ‘wet’ season began in October).

I said Wednesday the coast was much more likely to see rain than Palm Springs. That still holds true.

If we get anything it will be tiny. In the desert that’s enough to perk ears.

Rain For SoCal, Again

Once again we’re right on the 3-hour flash flood line. I expect some flooding. Homes in burn areas will be threatened by mudslides. A few inches of rain probable through this region.

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Helaine saw the hashtag #stormageddon touted on TV a few minutes ago. SoCal is bracing… again. Is there some weird secret competition with the East on weather?

“Yeah… well… rain!”

Actually this storm looks very un-SoCalish. The radar from Vandenberg AFB shows a squall line out front. The HRRR agrees. The squalls remain intact as the line slides down the coast. Embedded thunderstorms are entirely possible.

We’ll have rain most of the day Friday though the bulk falls between 4-7 AM. We’re right on the 3-hour flash flood line, again. I expect some flooding. Homes in burn areas will be threatened by mudslides. A few inches of rain probable through this region.

wind15min_t410m_f0945The heaviest wind comes with the heaviest of the rain. Winds will gust out of the south. The wind map to the left highlights the higher ground where winds will be strongest.

If there’s snow for our two nearby tall peaks it will happen late in the storm. My second winter and no white so far.

Father north, San Francisco proper has gotten 2-4″ of rain with some windward mountainsides getting over 7″.

So far, this is the awful winter everyone was praying for!

Not The Worst Storm–The Worst Time

Travel on Wednesday will be demanding. Air travel will present its own special hell.

Model Analyses and Guidance

I continue to look at the numbers for Wednesday’s storm in the Northeast. Not the worst, but certainly at the worst time. Wednesday. Day before Thanksgiving. You get it.

By this time all the TV mets should be saying the same thing. The guidance is straightforward and consistent.

The exact numbers don’t matter. There will be enough to plow inland. On the shoreline slushier.

Rain then snow in DC before dawn. By sunrise I-95 will be wet from Ft. Lauderdale to Fort Lee!

In Connecticut the action begins in the morning. Schools and businesses might have to make decisions before there’s anything falling.

The snow (and mixed precipitation on the shore) will continue until around midnight before tapering to snow showers and flurries.

Travel on Wednesday will be demanding. Air travel will present its own special hell.

Our spare bedroom is available.

Do You Miss Buffalo?

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I was just on the phone with my dad. We talked about the weather a little. He’s in Milwaukee where it’s 29 with a wind chill of 22. My office window thermometer shows 72.

“Bet you’re glad you’re not in Buffalo,” he said.

I am.

766 Auburn Ave   Google Maps

I lived here, at 766 Auburn Avenue (Google streetview link) in the third floor apartment. It was a beautiful one bedroom with no insulation and enough water pressure to take a shower if no one in the other two apartments was! During the summer we were woken by squirrel races on the roof.

Those who live in Buffalo do so by choice. Anyone who wanted to leave left a long time ago. There is a survivor spirit among the residents.

It is a really nice, liveable city. Real estate is very reasonable. Summers are magical. Winters are hellish.

Starting in mid-November a thick veil of low clouds descends upon the city. This is the beginning of the process that spawns Lake Effect snow. It’s convection, like bubbles in a pot of boiling water. It will remain mainly cloudy with a handful of exceptions until spring.

This time of year the Great Lakes are warm and the flow through the atmosphere cold. Warm air near the lake’s surface is drawn up, condensing as it cools. Clouds form, often dropping snow.

Lake Effect season begins suddenly. The start is when the potential for big storms is greatest… as we saw this past week. Once Lake Erie freezes the process shuts down.

Lake Ontario doesn’t freeze. Sorry Syracuse.

For a real Lake Effect event, winds must be aligned through the atmosphere often parallel to a lake’s longest dimension.

These storms are VERY localized. The physics involved in Lake Effect snow is very similar to summertime thunderstorm formation. In fact, sometimes thundersnow is part of a Lake Effect storm.

Think “thunderstorm downpour” of snow… except instead of moving on, the storm continues for hours or days relentlessly.

aurora

This graph is from East Aurora, NY. Under land use it’s marked, “Urban.” People live there. That’s over 30″ of snowpack with a water equivalent of 5″.

The edges of Lake Effect storms are well pronounced. You drive out of Lake Effect snow like you drive out of a summer thunderstorm. And these boundaries stay in place as long as the wind doesn’t shift.

No one can cope with this much snow. No one is equipped, even those areas that get as much as 200″ of snow a year!

“Yes, Dad. I’m glad I’m not in Buffalo.” But I don’t regret a day of living there.

Buffalo And The World’s Weirdest Weather

The photo at the top of this entry is Buffalo, Wednesday afternoon. The Sun is shining brightly.

Wondering where the snow is?

Elmwood-Avenue

The photo at the top of this entry is Buffalo, Wednesday Tuesday afternoon. It’s my old neighborhood on Elmwood Avenue. The Sun is shining brightly.

Wondering where the snow is?

robhimself793: I’m about a mile from the snow band, I have very little snow, maybe 6″. Just a mile south and people have 3 feet.

You’re seeing one of the more interesting aspects of Lake Effect snow. It is VERY localized. There’s heavy snow just a few miles from where this image was captured.

Lake Effect snow is the product of convection. Heat and moisture are transferred upward into the clouds from the relatively warm lake. You can see that in this time lapse of Lake Erie, one of the coolest pieces of weather video I’ve ever seen.

Heavy Lake Effect snow needs cold wind roughly parallel to the lake to get going. The resulting storm forms slender ‘streamers’ which reach out from the lake. They are often just a few miles wide, with flurries at the edges and white out conditions in the middle!

Near the Great Lakes it’s possible to drive from no snow to 4″/hour conditions in just two or three miles! These bands can stay stationary for hours, or even days!

Buffalo gets a lot of snow each winter, over 90 inches! Because of Lake Effect there are heavier snowbelts south of the city. People in Buffalo scratch their heads why anyone would want to live there, as we scratch our heads over Buffalo.

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Continue reading “Buffalo And The World’s Weirdest Weather”

Sometimes I Hate Knowing The Future

Meanwhile, as a forecaster (even if I do it just for fun right now) it’s sad to see tragedy unfold in slow motion. I didn’t know exactly where the flooding would be, but what we’ve seen the past few days was expected.

Deserts flood often.

phoenix flooding

Hurricane Norbert is a weird duck. It was a powerful hurricane. Then kryptonite. Cool water! Norbert deflated like a balloon.

THIS IS THE LAST FORECAST/ADVISORY ISSUED BY THE NATIONAL HURRICANE CENTER ON NORBERT.

norbertMonday at 2:00 AM the Hurricane Center washed its hands. Norbert had ceased to exist.

Except, of course, nothing ceases to exist. It just shape shifts a little, takes on another form.

Norbert is now a flooding rainstorm. I was scared this was going to happen.

On Saturday I wrote:

This could result in heavy rains and life-threatening flash flooding in these areas during the next few days.

COD Meteorology    NEXRAD Single Site Radar DataThe Mexican state of Sonora and extreme southern California and Arizona seem most susceptible.

I underestimated the scope. Phoenix broke it’s record for single day rainfall. There was more flooding farther north.

Meanwhile, as a forecaster (even if I do it just for fun right now) it’s sad to see tragedy unfold in slow motion. I didn’t know exactly where the flooding would be, but what we’ve seen the past few days was expected.

Deserts flood often. Their sparse rain comes in a very few intense storms. Water rises very quickly especially where there are steep mountains–as there are in the Southwest.

By the point my colleagues and I knew what was about to happen it was too late. Beside that our forecasts weren’t specific enough. Weather forecasting isn’t yet at the point where we can zero on a specific flood basin more than a few hours in advance.

Let’s Look At Clouds From Both Sides Now

If it looks like the clouds are boiling, just like a pot of water on the stove, it’s because the dynamics are very similar. Heat is being transferred upward through convection.

NWS EDD

We seldom get the big picture of what’s on the radar by just looking at the sky. Not today. Today is different in SoCal.

The atmosphere is unstable on the the other side of the Santa Ana Mountains, around 30 miles east of me. That’s where the radar (at the top of this entry) shows strong thunderstorms.

What’s striking in the time lapse below are the mid and upper levels of the clouds producing the storms. There are no clouds in the way blocking my view.

If it looks like the clouds are boiling, just like a pot of water on the stove, it’s because the dynamics are very similar. Heat is being transferred upward through convection.

The heavy rain and lightning bolts are out-of-sight behind the mountains. Here, I only see the signs. Everything is moving north and will soon be gone.

The Weather Websites I Use

This is my every once-in-a-while weather website recommendations. These are not the only sites with this data, just the ones I favor.

I’ve been forecasting the weather over thirty years. There have been a boatload of changes and improvements. We used to spend a fortune acquiring data at Channel 8. Now it’s all online and free.

This is my every once-in-a-while weather website recommendations. These are not the only sites with this data, just the ones I favor.

HRRR Model Fields   ExperimentalI use a lot of government data and government sites. They are not the splashiest, but they’ve got just about everything.

For models like the GFS or NAM.

For the short term, high res HRRR. The user facing side of this site is awful, but the HRRR is worth using.

NWS EDDFor greatly customizable maps on the fly, it’s EDD, again from NOAA. EDD has the feel of a freight elevator hung on a building under construction. Nearly everything works, but you’ve got to watch your step. EDD often requires a page reload to clear its foggy head.

A lot of what EDD does Wundermap does too, plus it has the European model! Wundermap is from Wunderground, weather geeks online since the Internet was young. They’re now owned by the Weather Channel’s parent company.

Severe Weather, SPC. The mesoscale analysis section of the site is crazy. You can delicately slice and dice the atmosphere looking for the signs of severe weather.

An admission. I don’t understand the significance of everything they make available.

For tropical weather I hit Dr. Bob Hart’s site at Florida State for individual models and Wisconsin for spaghetti plots.

The most valuable item from the Hurricane Center is the tech discussion. The lead forecaster describes the factors weighed making the forecast. It’s a different url for each storm, but you can find the discussion from their home.

By the way, for anything… and I mean anything that comes from the weather service in text form, I run to the Iowa Environmental Mesonet site.

I wish stuff would come faster. I wish maps would get larger. So many are still sized for a world where 800 pixels across was wide.

Sultry Summer Nights

WunderMap®   Interactive Weather Map and Radar   Weather Underground

You’ve heard of people who can sight read music? I can sight read weather observations.

Currently in New Haven it’s 73&#176 with a dew point of 70&#176. Relative humidity calculates out to 90%. I instinctively understand how that feels.

Bridgeport is 73/70, New London 70/68, Chester, Meriden and Brainard are all 72/70. Sticky.

The map above shows dew point and relative humidity at 11:00 PM EDT. I remember nights like tonight. Like living in a warm wet towel.

It’s not raining everywhere in Connecticut, but again, I remember nights like this. Even where there’s no rain falling it’s moist.

Visibility is down. Not fog as much as clouds and mist.

I liked sultry summer nights. Another thing to miss.

Now It’s Tropical Storm Arthur

After grazing the North Carolina coast Arthur will be picked up by a midlatitude front and ushered to sea. Friday’s New England rain will be enhanced (intensified) by Arthur’s moisture. That’s especially true in Eastern Connecticut and more so in Rhode Island and the Cape.

Atlantic TROPICAL STORM ARTHUR - Google Maps

Invest 91 became Tropical Depression 1, which is now Tropical Storm Arthur. I can’t not look!

Early season storms are usually wimps. Not always. Remember Andrew!

Intensity guidance, among the poorest prediction guesses we make, says Arthur will briefly become a hurricane on Friday. I expect no hurricane force winds onshore.

The spaghetti strands continue to be tightly clustered. A good sign, especially since the impact to Connecticut (where many of my friends still live) should be minimal, but still significant.

After grazing the North Carolina coast Arthur will be picked up by a midlatitude front and ushered to sea. Friday’s New England rain will be enhanced (intensified) by Arthur’s moisture. That’s especially true in Eastern Connecticut and more so in Rhode Island and the Cape.

By Saturday Arthur’s east of Cape Cod and steaming away. The weekend is saved in New England and elsewhere!

Remember: Though I do follow tropical systems and post when I can, you should depend on a meteorologist who works fulltime watching your weather. I am flattered people still value my opinion, but I shouldn’t be your ‘final answer.’ – Geoff

The First Tropical Depression Of The Season

This path, taking a tropical system to Cape Hatteras then paralleling the east coast offshore, is fairly common. It’s usually well predicted.

al012014

TD 1 has formed off the coast of Florida. I posted something about it on Facebook a few days ago. At that time the computers were stumped. Each model took the storm a different way.

Things have changed!

The spaghetti in this spaghetti plot is tightly clustered. Even the projected waypoint times closely align. This is what a spaghetti plot is best used for. The closer the alignment the more likely the forecast is good.

This path, taking a tropical system to Cape Hatteras then paralleling the east coast offshore, is fairly common and normally well predicted.

Tropical Depression 1 should become Tropical Storm Arthur. Graduation to hurricane is less likely.

Gray And Gloomy

In SoCal people look forward to these gray days as a break from our endless sunshine. An OC native I spoke to yesterday was curious if I missed rain?

Right.

I wanted to say, “You’re nuts.” I held my tongue.

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When I got up this morning (OK–it was afternoon. So shoot me.) the sky was gray. Not as bad as the photo (above) from the Mt. Wilson camera… but still gray. That’s not unexpected this time of year. May Gray is a well worn California phrase.

As it turns out, what looks like typical SoCal marine layer cloudiness is anything but! There are moderate to heavy radar returns from Central and Southern California.

The NWS office in San Diego describes it this way:

SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE MOUNTAINS AND DESERTS THROUGH THIS EVENING…WITH ISOLATED SHOWERS AND THUNDERSTORMS POSSIBLE WEST OF THE MOUNTAINS.

cali-radarThere are reports of street flooding in San Diego. Storm drainage isn’t very good in most older neighborhoods. It doesn’t take a lot to flood.

Even though these cells are moving in my direction it’s likely few (if any) will get here. The mountains east of us enhance the rainfall on the desert side, then stabilize the airmass as it moves back to lower elevations.

In SoCal people look forward to these gray days as a break from our endless sunshine. An OC native I spoke to yesterday was curious if I missed rain?

Right.

I wanted to say, “You’re nuts.” I held my tongue.

Actually, I feel gypped on days like today. Stupid attitude, but it is what it is. My mind has independently decided it’s supposed to be sunny and mild every day. I have no control over the letdown I truly feel.

By tomorrow we should be back to normal.

May Gray, June Gloom

Every area has its own weather quirks. They all follow the laws of physics, often through interaction too complex for humans to fully understand. Take this afternoons clouds.

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Even Californians complain about the weather. We should be ashamed of ourselves!

We have one of those potential kvetch times on-the-way. It’s the seasonal California May gray and June gloom. We’ll be waking to cloudy skies for most of the next week. They disappear by noon. This type of weather happens sporadically through summer.

In the case of coastal California, the offshore marine layer is typically propelled inland by a pressure gradient which develops as a result of intense heating inland, blanketing coastal communities in cooler air which, if saturated, also contains fog. The fog lingers until the heat of the sun becomes strong enough to evaporate it, often lasting into the afternoon during the “May gray” or “June gloom” period – Wikipedia

We’re over 10 miles inland. It’s not as bad as for coastal dwellers. Of course, they live on the California Coast. They’d better not complain. Ever. About anything.

This weather scenario wasn’t something we were looking for in Connecticut. Here, it shows up nicely on the forecast models. At the top is a BUFKIT readout from tonight’s 00Z GFS for KSNA, John Wayne Airport in nearby Santa Ana (Clicking the image will give you a much larger, much more readable look).

BUFKIT is an amazing program for visualizing weather data. It was developed at NOAA and is free, as is the data it uses.

With maps you see a large area for one specific time. With BUFKIT you see one specific place over a period of time. Go ahead–reread that.

There’s a lot going on, but what I’m looking at is at the bottom of the image. The lines are isohumes–lines of equal humidity. The cloud producing marine layer isn’t thick. On most days it only goes up 2,000 feet. It produces low, dense overcast. Sometimes there’s drizzle.

The marine layer forms in the evening and fades through the morning.

Every area has its own weather quirks. They all follow the laws of physics, often through interaction too complex for humans to fully understand. Take this afternoons clouds.

I Sure Talk About The Weather A Lot

I talk about the weather so much because of how shockingly different it is. It’s much better than I hoped for–and I knew the numbers. Granted, this was an exceptional winter.

Most easterners think of a warm climate and think Florida. It has a humidity based economy! The Los Angeles/OC/San Diego corridor is dry. Our dew point hits 60 a few times a year and then briefly.

I posted this on Facebook Thursday afternoon:

On the patio. We went to 101 today, but with 4% humidity. Down to 81, but very comfy w/little breeze and low humidity. A/C now off.

The comments started flooding back. There’d be more, but some people are bothered by all the notifications you get when you comment on my wall. I hate that too&#185.

One Facebook friend said:

Something fun and funny about your casual weather posts.

I talk about the weather so much because of how shockingly different it is. It’s much better than I hoped for–and I knew the numbers. Granted, this was an exceptional winter.

Most easterners think of a warm climate and think Florida. It has a humidity based economy! The Los Angeles/OC/San Diego corridor is dry. Our dew point hits 60 a few times a year and then briefly.

A typical winter has no cold, no snow and little gloom. Nearly all our rain falls in winter. Rainy days in SoCal cause the same tumult as Connecticut snow days.

Low humidity and relentless sunshine are our two most obvious pluses. Top-10 Chamber of Commerce days back in New England are every days here! Sky blue. Birds chirping.

My concept of temperature has to be re-calibrated. 100&#176 feels more like 85&#176.

We moved for the weather (and there’s that little thing of proximity to the child). We got what we wanted and then some.

&#185 – If you comment on my blog you won’t get notifications unless you ask for them.