Understanding weather forecast - question

[DeeJay]

Looking at the weather forecast for my area, it shows that at 2pm, there's a "chance of rain" with the probability listed at 20%. At 5pm the forecast is for "rain" (not "chance of") but the probability is still listed as 20%.

So what's the difference?

[slackmaster]

1. Both mean the same thing - It's going to rain somewhere, and any particular location has a 20%...

...chance of receiving measurable rain.

[Drale]

2. 20% is a low probably but alot of times

when they say a chance there's only a chance and when they say rain with a probably of 20% that means that 20% of the area could be covered by rain.

[Motown_Johnny]

3. .

I am guessing here....


It has been my understanding that the percentages listed refers to the area in question.

For example, your 20% chance of rain means that 20% of the area which that forecast pertains to has a chance of rain. Then the rain 20% means that 20% of that area will actually get rained on.



But I could easily be wrong.

[DeeJay]

6. I'll buy that. Thanks. n/t

[RUMMYisFROSTED]

4. Sage advice:

"Look out the window."

[DeeJay]

5. Time travel too?

Look out the window in the future, now?

Tell me how.

[RUMMYisFROSTED]

7. Look out a window into the prevailing breeze....

...note the weather...

...look at the horizon behind it...

...note that weather...

...combine the two, allowing for the speed of the wind, for a future forecast...

:patriot:

[petronius]

8. Here's a FAQ from the NWS (reply #1 is correct)

http://www.srh.noaa.gov/ffc/?n=pop

So, every point in the forecast region has a 20% chance of receiving measurable precipitation, i.e., there's a 20% chance it will rain somewhere.

The difference in verbiage may just be forecaster's choice, and they went for a bit of variety, or the 20% PoP may be rounded up in the first case and down in the second. :shrug:

[Scuba]

9. It means...

...they don't have a clue, but suspect it may rain somewhere, someday.

[DeeJay]

10. LOL. That's my experience.