Just Add Water: Looking at the Record-Breaking 2022-23 Winter at Tablas Creek

Sometime around 10:45am on Tuesday, March 14th, we blew past our previous record for our wettest-ever winter (42.85", if you're curious, recorded in 2004-05). By the end of that day, we were at 44.33". And we've had ten additional days of measurable rainfall since then. All told, we're at 49.01" of rain for the winter, roughly double our long-term average. After the last three dry years, it couldn't be more welcome. A quick visual comparison to past years since 1996:

The way in which the rain came has been just as remarkable as its total quantity. We've seen 69 separate days with measurable rainfall, and 18 of the 22 weeks since the beginning of November have seen at least some rain:

Overall, the distribution of the rain has been fairly even, with either a break after a series of storms (as we saw in mid-December and again through much of February) or modest enough totals that the ground, creeks, and reservoirs were able to hold it (as through most of March). Of course, there is that spike in early January, where we saw nearly 20 inches of rain in three weeks, capped off by six-inch day on January 9th. That was when Las Tablas Creek burst its banks and the flooding in Paso Robles made national news.

In addition to being wet, it's been cold. OK, not New England cold, or upper Midwest cold, but cold for California. Over the last four months, since the beginning of December, we've had just three days where the high temperature has made it into the 70s. More than two-thirds of the days haven't even broken into the 60s. That's really unusual for Paso Robles. And we've had 63 frost nights, the most at least since 2010, which is as far back as the data I can easily access goes:

But taken together, the inconveniences have been relatively minor, and the positive effects are likely to be lasting and significant. I'll dive briefly into the impacts, roughly from most negative to most positive.

The negatives

In the short term, we've had to be closed six days this winter either because the roads were closed by the county or because they were so awash that we closed preemptively to keep our people and our customers safe. Adelaida Road was washed out about four miles east of us, but the county did amazing work in getting it reopened in about a week. There was a short-term hit to our revenue from being closed. But all those days were in slow times of year, so the impact wasn't too bad. If your travel plans were impacted by our closures, we apologize.  

All the rain has depressed traffic to Paso Robles compared to what we expect. And I understand! I wouldn't want to drive the California freeways in a driving rainstorm either. That's weather for hunkering down at home. Even when it hasn't been raining, the chilly temperatures haven't exactly suggested relaxing on a terrace sipping wine. So it's not surprising that our tasting room traffic this year has been off 19% compared to 2022, or that the rest of our region would be reporting similar results. But given how scarce we are on wines after low yields in 2021 and 2022, it's not a terrible thing for us to have people delay their trips. 

The equivocal stuff

It's been so wet that there have been several stretches where we took the flock of sheep out of the vineyard so they wouldn't compact the soil. Unlike last year, when we were able to make three passes through the entire vineyard thanks to the early rain and the ample January and February sun, we're still working on our second pass. Of course, there will be more moisture than we've ever seen as we head into the growing season. We're expecting to be able to cut and bale more feed for our flock than we've ever done before. That, combined with the extra growth that we're sure to see in the forests and unplanted blocks, means we're likely to have plenty for the sheep to eat later in the summer, when forage is usually scarce.

The very wet soils have also meant that we've been unable to get our tractors into the vineyard and so can't begin the process of mowing or disking that's usually in full swing by April. Although we've been moving away from tilling in recent years, we still think it's a good idea to get the weeds out from amongst the grapevines and to mow the long grasses so that we get good flow of light and air through the rows (reducing mildew pressures later in the year) and allowing cold air to drain (reducing our risk of frost). That's just not going to be possible in the short term. Thankfully, budbreak (and the frost risk that goes with it) is delayed.  

The positives

Speaking of budbreak, the most important determining factor for when grapevines come out of dormancy is soil temperature. Wet soils hold cool temperatures better than dry soils, particularly when even the sunny days are chilly. And this year's budbreak is later than any year at least since 2012. Just in the last day or two, we've seen the first tiny leaves. But what we've seen isn't widespread enough to really make for a good comparison, so it's possible we'll even end up later than that year's mid-April start when it all comes down to it. Given that our weather station recorded a low temperature of 29.2F yesterday and 30.7F this morning, I'm happy things are dormant. A later beginning to the growing season can help in two ways, reducing the duration when you have to worry about frosts (a risk here through early May), and pushing harvest into what is likely a cooler time of year (say, mid-September through early November instead of mid-August through mid-October).

The hydrology out here in the Adelaida District is complicated. Unlike the east side of Paso Robles, where there is a single shared groundwater basin whose levels are fairly easily measured, under our limestone layers lies a network of underground rivers, lakes, and small aquifers. By the end of December, our well levels had risen back up to their maximums. That has happened just about every winter. But unlike in many recent years, the saturated soils are continuing to replenish those water resources at the same time that the delayed budbreak and the wet conditions have meant that the draws on these water resources have been lower. That will surely mean more water available later in the year, which is something we can all celebrate. A look in some of our lower sections shows just how much water is still seeping out of these hills:

We know that all this water will be invaluable later in the growing season. Paso Robles is a stressful place to grow if you're a grapevine. The summers can be hot and punishingly dry. But our calcareous soils, which offer an ideal mix of water retention and drainage, can help mitigate that stress. Their structure allows them to wick moisture from the surface down deep as it arrives, and then to transport it back from wetter, deeper layers toward the surface as those surface layers dry out later in the growing season. Knowing that the soils are saturated as deep as they go gives us the best possible starting point as we prepare for the growing season.

Finally, we know that vine health one year plays an important role in the bud development of the grapevines, which has impacts on the vineyard's productivity the next year. So all this lovely water and the robust cane growth we're expecting should have a positive carry-over effect on the 2024 harvest as well. Given that we're so short on wine that we're having to sacrifice some of our core blends this year and scaling back allocations of all of our estate wines, a couple of productive vintages in a row would be very good news indeed.

We only need to look back at the 2017 vintage for an example of what can happen when a rainy winter follows a multi-year drought. We saw outstanding cane and leaf growth, with some blocks looking like jungles. It was our most productive harvest in the last decade, but with excellent chemistry from the good vine health. And it has made some of our favorite wines in recent memory, excellent for both reds and whites.

It might be a while until we see another winter with rainfall like this past one. Sure, it's led to some inconveniences. But those feel minor compared to all the positives we're expecting. Now, we just need to dodge frosts for another month. Fingers crossed, please.