How wrong can briefer be? A T-storm encounter in So Cal...

VWGhiaBob

VWGhiaBob

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VWGhiaBob
In the category of Lessons Learned...a recap of a flight out of Palm Springs yesterday. I am a heavy user of briefers and all WX data. This is a lesson in how wrong they can be...and one in how even pilots who plan plan plan can get into trouble. This is a lesson in how unpredictable weather can be, even in So Cal. It's not a criticism of our briefer colleagues or their tools!

For my flight from Palm Springs to Whiteman (KWHP) yesterday in my Cirrus SR22, there was zero convective activity noted in the morning on the Outlook and no mention in my briefing. I flew there and had a short lunch.

On driving back to KPSP, I notice a huge Cumulonimbus, torrential rains, and lightening directly on my route of travel...but clear in all other directions. Surprised, I look at live radar reports and there are scattered cells, with the big one being in the Banning Pass on the direct route.

So I plan my flight around the cells. I call the briefer and he says to divert South towards north San Diego. "To the North we have advisories and flight is not recommended." 10 minutes later I'm in the air.

But when I tell ATC about my route of flight, they say, "Flight in that direction not advised due to severe turbulence and active thunderstorm activity". I look toward the South, and she is right...no way.

Well...this is a circumstance where the moving maps display with radar AND Foreflight really helped, along with visual out the window. While in the climb, I plot a course to the North, just skirting some Restricted areas. This is into the area that 15 minutes ago was "not advised". The controller confirms my new route should work and looks clear of T-storms.

I make my way home...all the way to Victorville on the way back to Whiteman...a 30 minute trip took 90 minutes (so much for the 30 minute reserve rule!).

Perhaps those of you who are used to T-storms are smiling and know this is common. For this So Cal pilots, T-storms are rare, and yesterday's events were new for me. My lessons:

1. Don't get over confident in the data provided during your briefing.
2. T-storms can pop up totally unexpectedly.
3. Sometimes the modern technology REALLY helps.
4. No matter how well you plan, be prepared for a stress-out situation where you have to completely replan your flight while flying the plane (full disclosure...autopilot was my friend)

License to learn!
 
Glad you made it, w/o using that shiny red handle. :D

Living, and now flying, in the SE was a big change from SoCal. I have seen some pretty big Tstorm cells, and even lines, develop in <30min. Like the radar and visual is scattered clouds to a 20mi line of heavy CB/Tstorms causing gulfstreams, et al to divert.

So while the info the briefer had may have been 20-30min old and correct then those storms can develop and dissipate fast.

Or he had his map in track up and meant south not north....:D
 
It happens. They've been wrong about ice too.
 
Yup, I did a search near Placerville yesterday. Brief was clear and calm. A few showers formed just east of the search area, and turbulence picked up. Observation indicated it was thermal, getting launched by rising terrain with a pretty modest 10 knot west wind, so I judged it would take a while to build, and I was on the updraft side. So, I cut the east side off and modified the search pattern to avoid, and instructed the observer to keep an eye out for lightning, and that we'd bug out at the first sign. I also raised the search altitude due to the potential downdrafts (they turned out all to be quite modest as expected, but a couple of the updrafts exceeded 1000 FPM). The west side of the search area was much better.

Some three hours after leaving the search area, there was an obvious anvil over the area, clearly visible from SAC.

Damn KAP140s suck in the slightest bit of turbulence. I turned it off pretty quickly when we started getting bounced. The scanner was a tough as nails young woman, but I still didn't want to cause a mess back there, and George sure liked to waddle, so I hand flew nearly the entire thing.
 
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It has been interesting weather.. I live near El Monte Airport, and watch planes fly by in the pattern all the time... the change in the weather was a lot yesterday. On Saturday afternoon, it was clear, then within 20 minutes a very dark cloud formed overhead, rained very hard, thunder and lightening, rainbow and was gone... I was outside working on a VW bug and watched it form.

As a newly returning pilot, I have watched the weather a lot, and compared it to Garmin Pilot app... to see what real stuff looks like compared to the radar... even on driving trips, wondering if I could have flown.. Still have a lot to learn but always will have a backup plan ready.

When you come down from the high desert, what is your preferred path??.. I will be flying up to Utah this summer a lot and still working on the planning of the best route over the pass, especially with winds there.. I drive it every work day, so see it first hand on the ground and have not flown it yet.
 
Great post. Saturday morning, I woke to partly cloudy skies where I live. But Foreflight and SkyVector advised of MVFR. I went to the airport anyway thinking the clouds would lift. When I arrived, it had become VFR, so I began prepping for the flight. Before leaving the FBO, I checked Foreflight and conditions became IFR. Despite really wanting to fly, I scrubbed my flight as the weather was too variable, and I knew that winds would pick-up in the late morning and throughout the afternoon. I agree about having and using technology available to you.
 
Carefully when the weather gets squirrelly in the valley, normally it's chronic clear blue and 22, just a little windy and warm, but when it lets go in there, it can make for interesting flights, plenty of planes embedded in the mountains surrounding PSP
 
From the OP...forgot one lesson more lesson...

30 minutes of reserve is WAY too low.
 
Flying across Lake Erie (lengthwise) at night in marginal VMC (haze). I'm practically welded to flight services asking for current weather. He kept assuring me the lake was clear of convective. We had passed Cleveland about 5 miles offshore. I noticed the darkness ahead had an off color and was reaching for the mic to once again quiz flight services when a lightning bolt illuminated the darkness revealing a deep purple wall directly ahead going all the way down to the water. Obviously I turned away. After we were safely on the ground at KCLE I called FS and plaintively inquired as to what the bejabbers had happened. I was talking to the same briefer I had been with on the radio. He said the radar had been completely clear when he last briefed me and five minutes later "the lake just blew up" with cells all around me.
Weather happens.
 
Yesterday flying my SR22 there was airmets posted for turbulence above 18K ft, but nothing forecast below 18K. I did notice a couple pireps at 3K and 8K an hour prior to flying that made me suspicious and expect the worse. In my 800 hours of flying so far, this was the most constant moderate+ turbulence I have encountered. It intensified throughout the entire flight and I was unable to climb or descend out of it. My point is that things can happen that are not going to be mentioned by a briefer. I prefer to do my own research and as a result, I was semi prepared to see some bumps.
 
For sure!

Pireps > airmets

As for around PSP if those windmills are spinning worth a darn you're going to get rocked, especially nearing or going through the banning pass.
 
Sounds like summer flying here in FL. If you can't learn to either plan appropriately, skirt around the storms, or just divert and land when things look rough then you aren't going to get any time in during the summer. Unless you fly early morning and land by noon.

Every day I'd see big rain clouds at work and at night I'd be just hanging out and I'd break out my iPad, fire up ForeFlight or Garmin Pilot and see a mass of green and red over the whole flippin' state.

I've had my share of close calls with thunderstorms. Diverted and waited a few of them out. Be safe out there...and don't rely on either ForeFlight or Garmin to make decisions about where storm cells are located. The weather on those devices is delayed and can RUIN your day.
 
Summer flyin', had me a blast.
Summer weather, happens so fast.
 
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