BATON ROUGE, LA (WAFB) - Many people know that Baton Rouge's all-time record low is 2°, set on February 13 of 1899. However, how many of you also know the Red Stick's second-lowest all-time temperature of 7° was set the following day! In the modern record, the two lowest readings for Baton Rouge are 8°, set on December 23, 1989 and 9° set on the January 21, 1985.
Those four dates account for all the single-digit readings ever for Baton Rouge... thankfully.
With our current arctic spell, lots of people have been asking, "What is the coldest spell that Baton Rouge has endured?" Of course, the answer is largely dependent upon how one defines a cold spell.
Thursday evening's first Alert Forecast is calling for a Friday morning hard freeze in the low to mid 20s for Baton Rouge, followed by a light freeze for Saturday morning. With the temperature at Metro Airport having dipped below freezing before midnight on New Year's Eve, that will mean seven consecutive calendar days with freezes for the Red Stick.
Without doubt, this current run of consecutive days with freezes ranks among some of the coldest spells on record for the Red Stick, but it is not as rare as you might think. However, it has been a while since we have dealt with such an extended run. We have to go back to February of 2011, when the airport recorded an 8-day run of daily freezes.
A look back through the Baton Rouge records shows that 7-day stretches have occurred 11 times prior to the current spell. More notably (Figure 1), there have been three cold snaps with 10 or more consecutive days of freezing temperatures, with the most recent occurring in January of 2010.
However, even with these extended runs, there were relatively few times during those consecutive-day freezes when the temperature remained at or below freezing through the course of an entire day. For the vast majority of days, the temperature climbed above freezing for several hours or more.
We have mentioned this a number of times this week. Freeze impacts typically become far more serious only when the temperature remains at or below freezing for an extended number of hours. Long-duration freezes often produce more damage, even if the absolute low temperatures are only a handful of degrees below 32°. From a damage perspective, ice at 30° is just as potentially destructive as ice at 15°.
With that in mind, we looked for those events where the temperature stayed at or below freezing for 60 hours or more (Figure 2). Fortunately, those prolonged freezing spells are relatively rare for south Louisiana.
Unfortunately, we do not have access to hourly data for Baton Rouge prior to the 1940s. As a result, we can only approximate the duration of "Great-Grandaddy" freeze of February of 1899 as well as the bitter cold spell of December of 1932. In the end, it's highly likely that February of 1899 would display the longest consecutive run of freeze hours if the data were available.
We also note the brutally cold spells in January of 1962 and December of 1989 (highlighted with asterisks) were only briefly interrupted with temperatures above freezing for a handful of hours. In both cases, the temperature dropped back below freezing for an additional 15 hours or more, adding to the arctic misery.
Those that were in Baton Rouge during those winters are almost certain to remember them. December of 1989, the event heading into Christmas Eve of that year, is remembered by many as the "Exxon explosion freeze," the blast that reportedly broke windows miles from the plant. And for the older residents, January of 1962 is sometimes referenced as the freeze "when students walked on the LSU Lakes."
In effect, the January of 2018 freeze is certainly notable, but is far from a record-setter. That said, given the tragedies associated with an outbreak of house fires across the region, as well as the widespread infrastructure and utility woes resulting from this week's cold, it's likely that this extended freeze will be long-remembered too.