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’s A Big Deal Here

Meteogram Generator

We do a seven day forecast at KMIR. Yesterday I mentioned Day Eight. It got a shout out (as Day Seven) again tonight. That’s because there’s rain forecast next Thursday.

The actual value to rain in the Coachella Valley (Palm Springs area) is debatable. We average less than six inches per year. The majority of our water comes from an underground aquifer. It would be long gone if not supplemented by water piped in from Parker Dam on the Colorado River. Rainfall seeping down is a small piece of our specific puzzle.

Nature doesn’t provide nearly enough to support our population and the hundreds of thousands of tourists who arrive every week during the season.

Whether rainwater helps or not, people in the valley value it. Mentioning rain here is like mentioning snow in New England. It grabs your attention.

If you break down next Thursday’s rain forecast over Palm Springs, it comes to .06″. Tiny. Hardly noticeable.

A forecast for that small amount of liquid a week away is chancy at best, especially when you throw in:


Wish us luck. It will get my attention on every newscast.

Who Said I’d Be Bored?

Some computer models show around an inch of rain in Palm Springs by Monday morning. That’s a lot in a place that floods easily. I spent time tonight explaining ‘washes’ to the tourists and snowbirds watching.


I’m forecasting the weather for the Coachella Valley at KMIR. The physics of weather are the same, but there are different tools to use.

Satellite imagery is a lot more important here. Anything coming from the Pacific is out of radar range nearly all the way to the coast.

I’ve been looking at a plume of moisture from north of Hawaii curving up the Pacific then back down the West Coast. It’s the big weekend weather maker for SoCal. The only way to see it is from the bird.

Saturday, while it’s raining in LA and San Diego, there will be partly cloudy skies over Palm Springs with a few sprinkles. We are protected by steep mountains, some over 11,000 feet tall.

On Sunday the moisture heads in from the south. No protection there! That’s when we get the bulk of our rain.

Some computer models show around an inch of rain in Palm Springs by Monday morning. That’s a lot in a place that floods easily. I spent time tonight explaining ‘washes’ to the tourists and snowbirds watching.

On top of the rain we’ve got wind for Saturday and as much as a foot and a half of snow in some mountain locations.

Who said I’d be bored forecasting here?

Rain Is Different Here

In the burn areas, places that had fires in the last year or two, it will take much less for canyon walls to fall. The scrubby growth that held everything together was burned away.

People in scenic canyon homes are usually OK, not always. They always say they’ll rebuild.

When a storm approaches the Southern California coast, as is the case tonight, it’s a big deal!

Thank you weather.cod.edu

Rain leads the news in SoCal just like snow does in the Northeast.

Every area has some sort of natural Achilles heel. Ours is rain. Can’t live with it. Can’t live without it.

This is a semi-desert climate. We get our paltry rain in a very few large doses. The water is good for reducing fire danger and irrigation, but most of SoCal’s water comes from the Sierras, hundreds of miles away. Rain at my house isn’t quite as important as it seems.

The latest computer guidance says we can take around an inch of rain in an hour, up to three inches in six hours before we flood. Close call.

In the burn areas, places that had fires in the last year or two, it will take much less for canyon walls to fall. The scrubby growth that held everything together has burned away.

People in beautiful homes with spectacular views are usually OK, not always. Sometimes their houses fall. Other times something falls on their houses. They always say they’ll rebuild.

Irvine has a few large drainage channels carrying runoff to the sea. Always empty. That will change.

No snow for Santiago Peak–visible from the bedroom window. A quick estimate keeps the rain/snow line above 10,000 feet–higher than these mountains.

NERD ALERT — Feel free to skip the next paragraph.

In Connecticut I’d look for the 850mb 0C isotherm as a good rain/snow indicator. During this storm it will be close to 10C over me. These storms tend to be convective–so cellular. Rain amounts will vary greatly city-to-city.

Hopefully the storm’s mightest punch will be in the Sierras. If you start hearing of little mountain towns with a new feet of snow you’ll know we hit the jackpot!

Oh–people here can’t drive in rain. I’ll leave it there.

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?


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.


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?


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.


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

Not That I’m Kvetching

It is uncharacteristically hot and sticky in SoCal today. We’ve been here 13 months. We’re peaking!

Hot, sunny and sweaty

It is uncharacteristically hot and sticky in SoCal today. We’ve been here 13 months. We’re peaking!

Sunday at 1:00 PM PDT it’s 83&#176, 65&#176 dew point. In Connecticut, where I spent three decades, that’s an average summer day. Here it is unusual.

We’re 8&#176 closer to the equator. The Sun is 8&#176 higher in the sky. Its path to the ground is more direct, its effect much more pronounced.

The Sun in New England never gets as high in the sky as it does during the summer in SoCal.

We had a little rain yesterday. Probably not the .01″ needed to count. There are rules.

In San Diego, Kristen Cusato said they led with rain on her 10:00 PM news on KUSI. I don’t think she was joking.

A quick check of the forecast models says we stay sticky for a few more days. The next real rain doesn’t come until Thanksgiving, maybe later.

Not that I’m kvetching.

Continue reading “Not That I’m Kvetching”

And It’s Raining

“THE SNOW LEVEL IS CURRENTLY AROUND 6500 FT AND WILL DROP TO 4500-5500 FT BY SATURDAY MORNING. A LIGHT DUSTING IS EXPECTED AROUND 5000 FT ELEVATION.” That’s NWS/San Diego shouting in all caps. We can see Santiago Peak from the bedroom window, elevation 5,689 feet. I want to see it white.


Friday night in SoCal and it’s raining. Two lines of showers are moving down from the northwest. The first, lighter, line is nearly through. The next piece is just now moving out of LA.

We don’t get much rain here. Duh. The entire state is suffering through a drought. We are being asked to do less than I would have expected!

Since we came last June, as far as I can tell, all the rain we’ve had has been convective. Bigger drops. Instability. The dictionary definition of showers refers to a convective origin. There might be some lightning with this next round of showers.

I’m not a big fan of single site radar here. Back in Connecticut, I’d often isolate the Upton or Taunton radar to look for detail. Here, the three radars that overlay my house constantly show different returns for the same system! It’s crazy, but understandable considering the terrain. West Coast Geoff uses a lot more composite views. The radar at the top is from College of DuPage–a great weather site.


That’s NWS in San Diego shouting in all caps. We can see Santiago Peak from the bedroom window, elevation 5,689 feet. I’m waiting to see it white.

Because of the topography there are lots of places where you can see 50 or more miles away with the naked eye. It is strange to drive around with the top down, looking up at snow covered peaks.

Bad weather doesn’t last. Tomorrow’s supposed to be back up near 70&#176.

Weather still fascinates me.

I’m This Storm’s Spectator


You will have to excuse me tonight but I’ve become obsessed with our upcoming weather. This is a first for me. My first real California ‘winter storm.’ I’m trying to gauge how pre-game coverage matches what really happens.

Viewers often accuse TV stations of hyping weather for ratings. I didn’t think we did, but this is an opportunity to watch as an outsider.

The late run of the GFS is VERY wet through the weekend. More rain than we’ve had in the last year!

For 28 years I lived in Connecticut. The hills there were more gentle than California’s steep slopes. These amplify rain’s effects. Most people are surprised to see the width of some of our washes (dry river beds). The mountains will fill those washes very quickly.

But, again, I haven’t experienced this first hand. Most of my SoCal weather knowledge is book learning and observing from afar.

Where there have been large fires, where brush hasn’t yet reestablished itself, expect landslides. Truly, insult added to injury. Haven’t these people had enough?

The vast majority of hills will remain intact. It’s just tough to say which ground is solid at any given moment.

I can’t imagine the big stuff will be widespread. We had around 800,000 without power in Connecticut after Hurricane Sandy. That seems very unlikely. Widespread outages of any number seem unlikely.

The main thrust of the first wave of rain is still offshore to the northwest of us. The GFS says .42″ at John Wayne in Santa Ana, with most centered around morning rush Thursday.

Round two gets here early Friday. For this the GFS says 3.349″ at Long Beach over 48 hours or so&#185. That’s a huge amount of rain for this place to absorb. It won’t be absorbed gracefully or easily.

The good news is there are few basements to flood!

&#185 – QPF, how much we’ll get, is the least accurate surface forecasters make. Giving it to the thousandth of an inch, as I did, is ridiculous.

Graphic courtesy coolwx.com

Rain Coming And Folks Are Excited


“It will be good for the state.” Those were Helaine’s words a few minutes ago. We were talking about the threat of rain in SoCal. We’ve had hardly any since last year’s rainy season–also a dud.

The image above is a screengrab from the afternoon GFS, using BUFKIT. If you want to know what kind of person I am, I find it fascinating. I like charts, graphs and numbers. They like me back!

I’m not going to be a whiner. Drought sounds and is bad. However, our infrastructure was designed knowing we get droughts. It needs much less than normal rain to work properly. No one is being forced to conserve.

We will finally end the fire season. That will be a relief to many. California has a tendency to burn.

Our first rain comes Wednesday evening. A cold front off a low hitting the California Coast near the Oregon border is the trigger. Not a lot. The GFS says around a quarter inch.

Meteorologists are lucky here. I’ve read and seen all sorts of quantitative precipitation forecasts (QPF). It’s our least accurate prediction. They’ll all be wrong, but unlike snow, no one will check up on them.

The rain (and snow) should be significantly heavier farther north, including the Sierra Mountains. They are our sponge! Snowfall in the mountains is slowly released through early summer. Much of what would run to the ocean now flows toward the Southland.

Water from the Sierras is California’s lifeline. It’s how we house people and grow crops in the desert! Like so many other spots in America, we have overcome nature to tame a place not naturally suited for any of what now happens on it.

The second wave of rain arrives Friday morning. The GFS shows three inch range, much more than this area can easily perc. Flooded intersections and slow traffic will follow. Thunderstorms, less frequent here than back east, are possible with heavy embedded downpours.

NEXRAD is pretty bad here. Too much topography. There are lots of holes using individual radars. This is one place where composites help.

During these storms our temperature will stay in the 60s.

Friday’s deluge will taper to showers then some scattered drizzle under cloudy skies through Sunday. People here are looking forward to this brief change. I will miss my friend, the blue sky.

Like Paul Blart, Mall Cop


At 11:15 PM PST/2:15 AM EST

Observe and report. Like Paul Blart, Mall Cop, I’m observing and reporting.

First stop, radar. It’s active. Snow, identifiable by radar only recently, is the only precipitation being seen at the moment. It’s moving west-to-east.

Meteorologists call the radar’s targets, hydrometeors. Cool name.

We can detect rain, snow, hail, sleet, whatever. If a radar beam can bounce off it, it’s tracked.

Most times the radar is amazing. Not always. I’ve seen storms develop in an unusually bright patch of ground clutter. Surprise! Where did that come from? A once every few year event.

All my observing tonight is on the College of DuPage weather website. They carry nearly every product with well chosen color tables. Highly recommended.

The surface map shows the low pulling east, leaving New England. There’s more moisture following and colder temperatures. The snow isn’t quite finished.

Before ending this morning that additional snow will cover the slushy wet mess already on-the-ground. Up to a half foot more will fall in scattered sections of the Litchfield Hills all the way to the UCONN campus. Most areas a few inches less. Even less on the shoreline and near 395.

But still, look what it’s covering!

Oh–and windy and much colder.

The amount of forecast and observational data available is immense. New tools arrive all the time. For nerds like me, this is heaven. Forecasting in pajamas!

I Feel Your Pain — Still


“I love the four seasons,” said no one in the Northeast today. The weather sucks!

There’s already six inches to a foot on-the-ground in Connecticut.

With rain/sleet/freezing rain and then a turn back to snow, the pack will be wet, heavy and tough to clear.

I just traded texts with my niece Melissa in Milwaukee. She and husband Mark are supposed to fly Southwest to New York City tomorrow. Good luck.

New York City’s new mayor is in snow denial mode. Another attempt to blame the weatherman. It’s bipartisan. Everybody does it!

The mayor and Al Roker battled it out on Twitter this morning. Winter will do that to you. Everyone gets testy.

Southwest hasn’t cancelled flights for tomorrow yet. They will!

Will Melissa’s plane even make it to Milwaukee tonight so it’s available for a 6:05 AM departure? Will the crew have enough rest hours? How crazy will our nation’s air traffic system be?

I’m not sure what to do on a day like today? It’s 75&#176 and partly cloudy at John Wayne Airport. Out my window, totally blue skies. Should I just keep my mouth shut and hide?

I totally understand what folks in the Northeast are going through. It might seem like I’m rubbing it in. I’m not. My dues are paid-in-full.

Usually by mid-February, winter had gotten the best of me. And yet I knew there was more snow to come. There was nothing to do but grin and bear it and plan my escape.

More snow Saturday. Post photos. That’s as close as I’m getting.

The Snow I Won’t Miss

New Year’s Night. 8:47 PM PST.

COD Meteorology    Numerical Model Data

There’s a storm on the way to New England. There are one or two major storms there during any snow season. This will be one.

I’ve been working the numbers. It’s fun to forecast. I like maps, graphs and numbers. I can do it sitting in my chair here in Orange County.

I don’t miss the anxiety of forecasting. I know my fellow meteorologists sweat these out too. No one wants to be wrong.

At this hour radar from the Northeast is showing snow over Connecticut. Bradley’s been reporting light snow for over an hour. Most of the state is still quiet. The center of the upcoming storm is over Arkansas!

Here’s the setup: The low moves from Arkansas to the Northeast. A Canadian high will block the low’s northerly progress, but also provide an ample supply of cold air.

New England’s geography takes over.

As the low moves over the relatively mild (compared to land) ocean it will explode! A low’s strength is measure by its central pressure. The pressure will drop like a rock!

The prediction shows a rapid fall from ~1016mb to ~985mb. That will enhance both precipitation and wind! More of each.

Don’t be fooled. This isn’t a linear storm. There will be a long period of light snow, then the main course.

Thursday will be cloudy with snow showers and flurries. A few inches will accumulate during the day. If you have to drive you probably will, though you shouldn’t. The wind will being picking up.

After dark, windblown snow becoming heavy at times. Strong northeasterly winds. You’ll want to be safely home before this bad boy gets going.

Some areas might see a foot. 5-8″ will probably be the average.

The snow ends Friday morning. It will be replaced by bitterly cold air with many spots dipping below zero Saturday morning.

You don’t want to know what it will be like here in SoCal tomorrow.

Trying To Keep A Low Profile In This Weather


It came via Twitter early today.

@JRRN27 @geofffox Hey Geoff, bet you don’t miss this snow!!!! –

It’s true. I don’t.

And there lies the rub.

Will I piss off old friends if I talk about the weather too much?

Roll down the window put down the top
Crank up the Beach Boys baby
Don’t let the music stop
We’re gonna ride it till we just can’t ride it no more

>From the South Bay to the Valley
>From the West Side to the East Side
Everybody’s very happy
‘Cause the sun is shining all the time
Looks like another perfect day
– “I Love LA” Randy Newman

We were in the eighties today. Even now, at 7:30 pm it’s 64&#176. Three of the next seven days are forecast over 70&#176. Six of seven will beat 60&#176.

Like most people who’ve moved, Helaine and I keep track of what’s going on elsewhere. The Internet makes that easy. I’ve been watching the cold and snow where my sister and folks live near Milwaukee and this weekend’s weather in Connecticut.

Snow is not a singular event. It takes different skills to navigate it at different stages.



Better forecasting has changed how people deal with snow. Years ago snow was often a surprise. The exact accumulation might be off, but a forecast of snow today is nearly always followed by actual snow!

If you’re scared of driving in snow, you no longer have to! You can plan ahead. That’s taken a lot of people off the road in storms.

More snow is likely early Tuesday in Connecticut. It will be light, but of a long duration. That means additional inches turning dirtying snow back-to-white!

SoCal residents have little tolerance for any deviation from sunny and 70&#176s. It’s funny to see people in winter coats when it’s in the fifties. Scarves too.

My daughter confessed she enjoyed the last rainy day. It was a change from the monotony of blue skies.

I will resist, but I can see how that happens. It’s only rained parts of five days since we arrived in late June.