Archives for posts with tag: frost advisory

We were under a Frost Advisory last night. That’s the warmest of the cold-weather cautionary notices issued by the National Weather Service. It indicates that temperatures may drop into the range of 36 to 33 degrees over the duration of the advisory.

Was there any real threat? No. The overnight low forecast for our area was in the upper 30s, at the upper end of the advisory scale. Frost was possible, especially at daybreak, but not very likely to occur.

Did I cover the garden anyway? Yes. Even as the likelihood of frost or freezing temperatures diminishes, the consequences of their occurrence increases. The farther along the vegetables are, the more exposed they are to damage. Also, the later in the growing season that damage occurs, the larger the investment (of time, energy, materials) that is lost.

It’s a good example of risk analysis. Moderate likelihood multiplied by high consequences produces moderate risk which can be mitigated with low cost (throwing plastic sheeting over the planters is easy, provided I get the warning in time). Overall, the risk to the garden is low.

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Mother Nature continues to be a bit confused about what season it is.

After a glorious weekend when temperatures reached through the 70s and into the 80s, we awoke this morning to a one-inch-thick layer of snow and ice which fell overnight.

Like the winter storms before it, the snowfall cloaked the still-leafless trees in a shroud of white. It has been long enough since the last one that I can again appreciate the beauty.

Sadly, however, I could not escape the need to sweep the walk and scrape the cars, tasks made more difficult by the persistent cold temperatures. That I do not appreciate. Nonetheless, it is forecast that the day will warm to above freezing and the snow should soon melt.

The planters are also blanketed by snow but I’m not worried about the seeds we planted on Sunday (see April 13, 2014). Probably nothing much has happened beneath the soil’s surface. The seeds will pause whatever they were doing and will resume when the soil heats up again. In effect, it will be as if the seeds were planted today.

There was a frost advisory two nights ago, a freeze warning last night and there is a freeze watch in effect for tonight.  This is what I would call a winter preview.  I’ll be relieved after next Friday—November 1—when the National Weather Service will dispense with these announcements.  At that point, we can expect that it will be cold at night, every night, until spring.  Frankly, the near certainty of it is much easier to deal with.

The only vegetables remaining in the garden are the eggplants and bell peppers.  The three eggplants still hanging on are smaller than I would like but are (I believe) ripe enough to eat.  So, yesterday, I harvested them (rather than risk their freezing).

There are still many bell peppers—almost a dozen—at various stages of development.  None are large enough to even begin to turn color; all are the traditional green.  To prevent their loss to cold temperatures, I snipped them off to take inside.  When I lined them up on the edge of the planter, there was one of almost every size.  If Goldilocks were joining us tonight for dinner, she would be sure to find at least one of them that was juuust right.

With nothing left growing, I decided it was also time to pull in the hoses and shut the garden down for winter.  I did this with no ceremony even though the action marks the end of the 2013 growing season and heralds the onset of winter.

Just before shutting down my computer this evening, I took one last look at the weather forecast.  Some people compulsively check the stock market and others keep close track of baseball (and other sports) scores.  I’m addicted to the weather.

I was rudely surprised to see that the National Weather Service had posted a Frost Advisory for later tonight and into tomorrow morning.  Where did this come from?  Yes, the forecast has been calling for cooler temperatures, with highs in the 70s and lows in the 40s and 50s, but frost?  Really?

And what am I supposed to do with this information, at such a late hour?  The warning was not posted until about 6:00 pm.  That gives me only an hour before the sun sets.

Not that more warning would have been particularly useful.  Although the number of plants remaining in the garden is diminishing, there are still several growing strong.  And all of them are either tall (e.g., the tomatoes and string beans) or spread out (the squashes).  It’s not like I can easily throw a tarp over the entire yard.  (Well, I suppose could do that, but it wouldn’t be easy.)

I imagine that some farmers will be firing up their smudge pots tonight.  A common sight in orchards and vineyards, these oil-burning heaters produce a high-volume of slow-rising smoke—some call it artificial smog—which I always thought enveloped the plants and slowed their cooling.

Turns out they work more like the large fans that other growers—such as an apple orchard we visited last weekend—will be switching on instead.  Both the heaters and the fans circulate the lower levels of the atmosphere, moving colder air at the surface upwards and bringing down warmer air from the overlying inversion layer.

I love the idea of having one of the monster fans in my backyard (I could connect it to my propane tank) but I suspect they are very expensive (no, I’m not seriously considering it).  So this time, we’ll take our chances and do nothing.  Despite the advisory, the forecast low is 44 degrees, well above freezing.  I’m not too worried but we’ll see how things look in the morning.

For the most part, the seedlings are ready to be transplanted to the garden but could use a few more days of hardening off.  Today, I put them out into full-sun for a few hours and will continue to do so, increasing the duration every day until the upcoming weekend.

Another reason to wait longer before setting the seedlings out is that the temperature still gets down into the 40s at night.  We haven’t had any more frost advisories or freeze warnings so there would not be much risk to transplanting now but it would not be very productive, either.  The growth of most of the plants would be stunted by the cool temperatures.

This is not to say that the seedlings are not anxious to get outdoors permanently.  Most of them are getting too big for their plastic pots and some have sent roots out through the drainage holes looking for water.  The crookneck squashes are particularly impatient to get into the garden.  A few of them have already started to form female flowers, which can be identified by the tiny proto-fruit at their bases.

Once again, the odds are against us.  Last night, the National Weather Service issued a frost advisory and tonight, a freeze warning is in effect.  We are more than a week beyond the official last expected frost date but as noted before, that doesn’t mean that frost or freezing temperatures are impossible, just that they are unlikely.  This late in the season, it should be very unlikely.

Have we entered a period of unlikely occurrences?  If I had a jar filled with uncooked rice and beans, would the two be perfectly separated, one layered over the other?  [See The Eyre Affair, by Jasper Fforde.]  Would now be a good time to travel into deep space?  [See The Hitchhiker’s Guide to the Galaxy, by Douglas Adams.]  Should I run out and buy a Lotto ticket?

Last night, I covered the most delicate seedlings in the garden—the romaine and red leaf lettuces—and tonight I will do the same.  But with a greater risk of freezing temperatures, I will also cover the west planter.  I should be able to get black plastic sheeting over everything except the peas who extend well above the top of the planter (even if their trellis was not in the way).  They will have to tough it out.

Even during the day it is colder outside than it is indoors (just like winter!).  Therefore, I am suspending the hardening off.  It’ll be like a snow day except that everybody has to stay inside.

Late yesterday afternoon, the National Weather Service posted a frost advisory for our area.  I didn’t see this until I checked the forecast at about 9:00 pm.  The advisory did not seem to make sense—the expected overnight temperature was warmer than 40 degrees—but just to be on the safe side, I covered the garden with a sheet of black plastic.  The effects of micro-climate should not be underestimated.

The temperature did drop into the 30s (but only just, at 39 degrees) so there was no real danger of frost.  Still, I imagine that the peas, carrots, turnips, radishes and beets appreciated the protection.  They have spent their entire (if short) lives out in the cold and probably envy their cousins (the tomatoes, squash, cucumbers, eggplant, bell peppers and basil) who have yet to venture outdoors.

Now that we are into the month of May, the risk of further frosty nights is rapidly diminishing.  It’s tempting to think that the threat has vanished but statistics don’t work that way.  No, there is still a non-zero chance of freezing temperatures but the probability has dropped below ten percent.