iFly GPS Forum

I noticed the same gray weather display.  How about an official interpretation from iFly, just for the record? 

Looking at the website that Jim suggested leads me to the same conclusion, that the gray area depicts clouds without rainfall, but I'd sure like to know the definitive answer.

While waiting for iFly to post an answer I did some more research on the gray shading based upon Jim's reference to the NWS radar site.  The site shows a dBZ bar across the bottom of the radar images.  Looking through the help screens (which IMHO aren't very helpful) it appears that the gray area is representative of a low level of dBZ return strength.  The text reqarding this is shown here. 

I've taken two screenshots of the same area over the Grand Canyon, one from iFly and one from the NWS Radar website.  They show the same gray areas.

Is there some way to make iFly turn the grey on and off without turning NEXRAD off altogether? Yesterday I was flying in an area south of DC with lots of ugly airspace--R-6611A, R-6612, and others--when my 740 started painting nexrad grey over the screen. The chart was still visible, but all the color seemed to be washed out, and it was rather hard to make out what was what. Then I noticed that if I zoomed in far enough the grey disappeared. For a while, and then it was back again.  I was busy flying and navigating, and didn't have the leisure to screw around with the 740 to figure out what it was doing and what NEXRAD was doing to it. There was no danger, of course; but it might have been awkward if I hadn't been familiar with the area. It would be comforting to know in advance if there's a remedy.

My iPhone was also running iFly, but with the EFIS at half-screen. The other half sometimes showed the cloud-grey, but not as dramatically as the 740 did. Or at least, that was my impression. I couldn't really make any clear comparisons at the time.

The 740 also popped up an error message--a network problem, I think--but that didn't seem related to the NEXRAD grey.

Here are a few pics taken from a small area of a GoPro video to give you an idea of what I was seeing:

1. No grey; all swell

2. Grey painting downward, from top to bottom (video magic!)

3. Grey fully painted

4. Grey screen with 740 error dialog

5. Error dialog, no more grey

6. Just for comparison, here's a later shot cropped from a still camera frame, showing the grey more clearly, more like how my eyes were getting it. The chart was hard to read.

I'll be grateful for any ideas!

P.S. It was a rather odd sky yesterday. There was a medium overcast, so the light was diffused and the air was very smooth; viz better than 10 miles, but seemed just slightly hazy; and the air smelled of dust, as if there was a sandstorm somewhere upwind. But I couldn't spot any cause in the WX info available.

P.P.S.The blackish mat draped over my left knee and shin is the latest of many attempts to prevent reflections on the 740's screen. It looks a bit odd, but there were almost no reflections at all, so I think it's a keeper.