The advance of cold front 43 It's leaving a rather turbulent landscape in much of Mexico, with a cocktail of heavy rain, strong winds, temperature drop and rough seas Right in the middle of the hot season and during peak tourist season for Easter. Although the calendar says spring, the atmosphere is behaving more like late winter, as happened last year. cold front 42.
According to various reports from National Meteorological Service (SMN) and Civil Protection authorities, this frontal system, accompanied by a polar air massa dry line in the north, low-pressure troughs, a trough at mid and upper levels, and the subtropical jet stream, is creating a scenario of severe weather in the north, northeast, central, east and southeast of the country, with special attention to areas such as Tamaulipas and Veracruz due to the "Norte" event and the strong waves; similar patterns were analyzed after the cold front 41.
How does cold front 43 behave and what makes it so intense?
El cold front 43 It moves from the northern border towards the Gulf of Mexico coastlinewhere it is combined with a dry line In the north, a low-pressure trough in the southeast and a trough at altitudeThis mixture of systems creates a highly unstable atmosphere, ideal for the formation of severe storms, hail, strong gusts of wind and even more severe phenomena such as whirlwinds or tornadoes in border areas, as seen in previous episodes such as the cold front 39.
La polar air mass associated with the front is responsible for sharp drop in temperatureespecially in northern and central states of the country. In mountainous areas of Chihuahua, Durango, Coahuila and Nuevo León Minimum values are considered, which may be around -10 ° CWhile the rest of the north and the high plateau are expected to experience cold mornings, unusual for this time of year; situations of extreme cold linked to previous fronts have been covered in reports such as the one on cold front 38.
Furthermore, the front not only brings cold and clouds: being pushed by denser air, it generates gusts of wind which in the north and northeast can exceed 60 to 80 km / hintensifying the feeling of cold and increasing the risk of falling branches, trees or signs, as well as the formation of dust devils in arid regions; this type of severe gust has been documented in analyses of the cold front 37.
At high levels, the subtropical jet stream It reinforces clouds with significant vertical development, so they cannot be ruled out. thunderstorms with hail In different parts of the country, especially in the north, east and southeast, where the humidity from the Gulf and the cold air descending from the north converge; similar conditions were observed during the cold front 33.
Heavy rains, storms and possible tornadoes in the north of the country
At the northern and northeastern MexicoCold front 43 combines with a dry line and very unstable air, resulting in a scenario of heavy rain, thunderstorms and severe wind. The SMN It highlights that the states most affected by this pattern will be Coahuila, Nuevo León, Tamaulipas and San Luis Potosíwhere precipitation can occur in the form of organized showers or short-lived but very intense storms; comparable impacts were analyzed in the cold front 32.
These entities are expected wind gusts of 60 to 80 km/h, accompanied by electrical discharges and possible hailstormsThe atmospheric conditions are also favorable for the formation of whirlwinds or tornadoesespecially in open areas of northern Coahuila and Nuevo León and in border areas exposed to the interaction between cold air and warm, humid air from the Gulf of Mexico; episodes with tornadoes and intense gusts are described in cases such as the cold front 30.
In parallel, the polar air mass linked to the front causes a strong thermal contrastWhile during the day the environment may be relatively mild, at night and in the early morning temperatures drop rapidly, increasing the risk for people in vulnerable situations or exposed to the outdoors.
The advance of the frontal system also reaches the Valley of Mexico and the east of the country, bringing cloudiness, showers, and cooler temperatures. Mexico City and State of Mexico Cloudy skies, intervals of showers, and wind with gusts of up to 50 km/hwith maximum temperatures around 26 to 28 ° C and minimums that can be around 10 to 12 ° Cgenerating a feeling of abrupt change after several days of heat; situations of thermal contrast are examined in notes such as the cold front 29.
Late winter storm in the east and southeast: Veracruz, Oaxaca and Chiapas in the spotlight
As cold front 43 moves over the Gulf of Mexico slope, the eastern and southeastern states become the epicenter of the most intense rainsThe National Meteorological Service (SMN) forecasts heavy to very heavy rainfall and even occasional intense in regions of Hidalgo, Puebla and Veracruzas well as in areas of Oaxaca and Chiapas When the system settles over the Gulf and acquires almost stationary characteristics; records of fronts with intense rainfall in that region can be found in the cold front 27.
En VeracruzThe extended 96-hour forecast indicates that the interaction of the front with a low-pressure trough, an upper-level trough, and the subtropical jet stream will cause episodes of heavy, very heavy and even intense rains, accompanied by electrical discharges and hailstormsThese rains can cause increased levels of rivers and streams, landslides, waterlogging and flooding in low-lying or poorly drained areas; scenarios of intense rainfall and flooding have also been described following the cold front 25.
El “North” event It will be especially relevant on the Veracruz coast and in the Isthmus and Gulf of TehuantepecWind gusts are expected 70 to 90 km / h, with waves that, depending on the day, can range between 1.5 and 4 meters highThis necessitates extreme caution in ports, beaches, and maritime activities, as the combination of wind and swell significantly increases the risk.
In the state of VeracruzThe different days of the episode show nuances: days with heavy to locally intense rainfall (75 to 150 mm) in the north, followed by other areas with rainfall strong to very strong (50 to 75 mm), while maximum temperatures may continue to reach 35 to 40 ° C In some areas, this creates a strong contrast between daytime heat and a cold or cool environment associated with the polar air mass and the north wind.
Further south, in Oaxaca and ChiapasThe interaction of the stationary front with moisture from the Caribbean and the Pacific will cause heavy to very heavy rainswith occasional episodes intense in ChiapasThe complex topography of the region increases the probability of landslides and mudslides in mountain road sections, as well as the rapid formation of runoff and flash floods in rivers and streams.
"Norte" wind event, high waves and risk on tourist beaches
One of the most striking effects of cold front 43 is the marking “North” event on the coast of Gulf of MexicoThe push of the polar air mass channels north and northeast winds over the coasts of Tamaulipas, Veracruz and further south, the Isthmus and Gulf of Tehuantepec in Oaxaca and Chiapas, causing gusts that can easily exceed the 60 to 80 km / h, and even reach the 90 km/h in more exposed sections; similar “Norte” episodes are described in the cold front 12.
These gusts not only affect urban and rural areas, where they can to cut down trees, poles or signsbut they also generate a high waves which seriously complicates maritime navigation and recreational activities along the coast. Waves are estimated to be between 1.5 and 2.5 meters along much of the coastline, with episodes in which the waves could increase to 3 or 4 meters in the Gulf of Tehuantepec and open areas of the Gulf of Mexico.
En TamaulipasThe State Coordination of Civil Protection has focused on Miramar Beach, the main tourist destination in the south of the state. There, the arrival of cold front number 43 over the weekend coincides with the start of the holidays, which implies tens of thousands of visitors in the coastal area. The warning indicates that the "Norte" will bring sustained winds of 35 to 55 km / h with gusts of up 75 km/h and a swell that will oscillate between 2 and 4 meters highNavigation warnings and recommendations have been published following previous systems such as the cold front 11.
These conditions imply a Direct risk to swimmers and small boatsTherefore, authorities recommend avoiding entering the sea while adverse conditions persist, and respecting the warning flags and follow the instructions of lifeguards and Civil Protection personnel. Pay attention to low-lying coastal areas, where strong waves and rain can cause hazards. flooding and coastal erosion.
Along the Veracruz coast and in the Isthmus of Tehuantepec, the "Norte" wind will be accompanied by heavy rains and a drop in temperature, creating a distinctly wintry feel for this time of year. Deep-sea, coastal, and fishing vessels have been warned about the High risk in open water, with the recommendation to limit outings and stay tuned to Port Authority announcements.
Rainfall distribution, extreme temperatures and associated risks
El cold front 43 leave a map of very uneven rainfall Throughout the country, some areas are subjected to veritable storms, while others experience only isolated showers. north and northeast, states like Coahuila, Guanajuato, Querétaro and Chiapas They are included in the group where they are expected heavy rains (25 to 50 mm)While Nuevo León, Tamaulipas, San Luis Potosí, Hidalgo, State of Mexico, Tlaxcala, Puebla, Veracruz, Oaxaca, Campeche, Yucatán and Quintana Roo They are located in the area of showers (5 to 25 mm).
On the other hand, entities such as Jalisco, Colima, Michoacán, Mexico City, Morelos and Tabasco they will generally isolated showers (0.1 to 5 mm)without ruling out some more isolated storms in mountainous areas. This distribution makes it clear that the strongest impact of the front is concentrated in the north, east and southeastwhile other regions maintain a more moderate or irregular rainfall regime.
Regarding temperatures, the scenario is very contrasting. On the one hand, the polar air mass is pulling values down in Chihuahua, Durango, Coahuila, Nuevo León and other highland states, with minimum temperatures near or below 0 °C in high-altitude areas and localized frosts. However, at the same time, a heat wave in sectors of Pacific, central and southernwhere they are kept maximum temperatures of 35 to 40 °C and even peaks of up to 45 °C in areas of Nuevo León, Tamaulipas and Guerrero.
This marked temperature contrast favors the appearance of severe phenomenabecause the warm, humid air collides with the denser, colder air advancing from the north, which can intensify storms and generate hail, whirlwinds or tornadoes and very strong downdrafts.
Main associated risks that the SMN and Civil Protection point out include urban and rural flooding, landslides in mountainous areas, fallen trees and billboards, damage to power lines Traffic disruptions are expected due to flooding, poor visibility, and debris blown by the wind. Warnings are also issued about possible service interruptions in areas where the storm hits hardest.
In high mountain areas of the central part of the country, the combination of the polar air mass and humidity even favors conditions for the snowfall or sleet on peaks like Popocatépetl, Iztaccíhuatl and Pico de OrizabaThis is unusual in a context of advanced meteorological spring, but possible given the intensity of the cold air and the current atmospheric circulation.
Given this situation, the authorities insist on the Importance of following official notices from the National Meteorological Service (SMN) and state and municipal Civil Protection units, especially in states like Tamaulipas, Veracruz, Oaxaca and Chiapaswhere heavy rain, strong winds, and high waves converge. The public is advised to avoid risky behavior, not to attempt to cross rivers or flooded areas, to secure objects that could be blown away by the wind, and to bring extra warm clothing, despite it being the warm season.
The episode associated with cold front 43 It is therefore shaping up to be one of the most significant of the season in terms of thermal contrast, maritime storms and rain in the east and southeast of the country, at a particularly sensitive time due to the high mobility of people for holidays and the presence of tourists on beaches and mountain areas.
