Hurricane Blanca is only the second named storm in the three-week-old Pacific Hurricane Season, but it’s already the second category four hurricane to form there in the past two days. The storm will slowly move towards the Baja Peninsula this weekend, after which it might or might not drench the American Southwest.
Blanca formed on the heels of Hurricane Andres, which reached category four status with 145 MPH winds early this week. It’s unusual—scratch that, record-breaking—that both storms reached major hurricane status so early in the season; the previous record was set by Hurricane Cristina one week shy of a year earlier. Sea surface temperatures in the region are much warmer than normal, which is the likely cause of Andres’ and Blanca’s explosive intensification.
Sitting a few hundred miles off the western coast of Mexico, the storm shouldn’t pose a threat to the vast majority of the country’s population outside of high surf and dangerous rip currents. The greatest threat at the moment will be the storm’s potential landfall near Cabo late this weekend or early next week, which is an areas still trying its best to recover from the damage left behind by Hurricane Odile last summer.
If you take a look at this forecast map from the National Hurricane Center—which I usually make myself but I accidentally deleted all of my QGIS data, bless—you’ll see that the storm is currently forecast to move north through the weekend, potentially making landfall on the Baja Peninsula before its remnants push inland towards the southwestern United States.
Hurricane Blanca is impressive on satellite imagery today, sitting stationary over warm waters in a favorable environment for strengthening—the storm was able to clear out its eye this morning, allowing it to reach category four strength on the Saffir-Simpson Scale with maximum sustained winds of 130 MPH. After hitting peak strength sometime today, Blanca will gradually begin to weaken as it pulls out of parked position and begins drifting northward.
If the storm stays on its forecast path, it could have bittersweet results for the drought-stricken southwestern United States. Take a look at these precipitable water values next week, which are way above normal for this region, let alone for this time of the year:
Precipitable water (PWAT) is a good way of measuring how much moisture is available in the atmosphere for thunderstorms to tap into—the values are measured in inches, and they tell you how much rain would fall if all of the water vapor in that column of the atmosphere condensed and fell as rain. Values higher than 1.0-1.5” are ripe for heavy, drenching rains that could lead to flash flooding.
However, the Weather Prediction Center, which issues precipitation accumulation forecasts, isn’t quite on board with the idea of heavy rains next week. Their latest seven-day forecast map—which, again, I would usually generate myself if I wasn’t such a chucklehead and deleted all of my data by accident—shows a general area of less than one-quarter of an inch of rain, which typically indicates widely scattered showers and thunderstorms.
Either way, it’s important for folks who live in desert communities in this region of the country to keep in mind that there’s at least the chance for heavy rain later this weekend and into next week. Some of the worst flash floods in the Southwest come from heavy rains brought on by tropical systems that made landfall in Mexico and kept moving north across the border. Never drive through a flooded roadway, especially not in Arizona—they can make you pay for your own water rescues, if it comes to that.