Maybe a weather alert radio?

I left the outdoor Christmas lights on and put some on the Meyers lemon tree, i also had some Agribon and covered the hydrangeas and potted Key lime. I like the Agribon because you can leave it on . i've used it now for three years it lasts . i even use it to protect seedlings from the occasional hot spell we have in SF. i buy it on e -bay.

It is supposed to be 41 degrees tonight, and so I brought some of my orchids inside. It was that cold Saturday morning without a warning, and but everything is okay so far. I think I will leave some of the orchids inside until it gets back to normal temps. This did not happen to me last winter. Some of the orchids need cool spells in order to bloom, but not this cold. I try not to collect ones that are not cold hardy, but I have a couple that stay inside all the time. I have them in a semi-protected area outside right now.

San Francisco and nearby cities are fine. You wont need to cover. Here in the inner eastbay, Its a closer call at 35f give or take. I will cover the mango,croton,delonix seedlings. Everything else I have wont need protection from lower- mid 30's.

Hayward was second warmest high for today -62 in the STATE. Santa Rosa hit 63.
So,we up north shouldn't get any surprise freeze. San Francisco might not go below 42f ...

You can use a recipe to do that with IFTTT. Scroll down on the linked page to the proper recipe.

Here is a link that might be useful: Ifttt weather reciped

Certain areas of San Francisco will frost, my north facing backyard will get frosty, so I do have to cover my citrus and bring some of the plants into the greenhouse for shelter, one potted hydrangea i forgot to cover , is a little frostbitten. i hope the cymbidiums will finally spike some buds, it needed the temperature drop. I did bring the masdevillas into the green house during the night and the potted Hawaiian Ti leaf plant. Wind Chill, burrrrr

Citrus?? They don't need any covering in SF. Even the NWS omitted the whole city from even a frost advisory.
The last time SF saw serious killing cold was 1990.

It was 26 last night here in SoCal, and Temecula woke up to snow on New Years Eve Day which hasn't happened in ten years! The kids were full of glee and snowmen sprouted in all the yards immediately. The mtn tops around us are still frosted and beautiful. So some of my more sensitive succulents, my little orange tree, bougainvillea and staghorn ferns, all have sheets thrown over them tonight.

Citrus virtually never needs protection in SF. I live about 30 minutes north in Novato. Our winter lows are typically around 24-25 degrees or so, much colder than SF. I never protect my citrus. At 25 degrees, my true lemons show some mild damage to the external leaves, but the damage is very limited and they recover quickly. The meyer is even more tolerant of cold temperatures than a typical (e.g. Eureka) lemon.

-Brett

Nil, that is pretty awesome and really versatile.

my meyers lemon is blooming profusely so i covered it, better be safe than sorry and not have another crop of lemons.

It got way below freezing the last couple of nights here in the Central Valley. I drug the Meyer Lemon, and it's huge pot, into the garage. Today was warm and sunny and so put it where it could enjoy the warmth and sun. Other than this one plant, I'm refusing to cover anything this year. Die and it won't get replanted. I'm tired of babying plants!

If you don't have this, you should get one. It will make your life so much easier! And if you only have the one plant to move now, it's a not so expensive.

{{gwi:2123693}}

Devault Enterprises Model # DEV3000P
16 in. Plant Dolly Terra Cotta

You can get them on Amazon or at many of the big box stores.

I have never heard of a service like that. It could only be a reference anyway. Your actual temp maybe higher or lower than the service prediction.