Ebiwujjo by’omuliro, Pyrocumulonimbus Downdrafts, n’enneeyisa y’omuliro ogw’omu nsiko ogw’ekitalo¶

Omuliro gw’omu nsiko ogwa bulijjo guvugibwa okusinga empewo ez’okungulu, amafuta amakalu, n’okusereba kw’ettaka, nga gutambula mu kkubo eriteeberezebwa abaddukanya embeera ez’amangu lye basobola okukoppa nga bukyali essaawa eziwera. Naye omuliro ogw’amaanyi bwe gufulumya amaanyi ag’ebbugumu agamala okutandika okukola enkola yaago ey’obudde, omuliro gukyuka ne gufuuka enneeyisa y’omuliro ogw’amaanyi ennyo ogufugibwa ebiwujjo. Mu ddakiika ntono, ebire ebiwanvu eby’omuyaga ogw’omuliro pyrocumulonimbus (pyroCb) bisobola okukuba kiromita 10 ku 16 (fuuti 33,000 ku 52,000) mu stratosphere, era empagi ezo ezigenda waggulu bwe zinyogoga ne zigwa, zikuba empewo ezifuluma ez’amaanyi g’omuyaga eza 90 ku 140 km/h (55 ku 85). mph) wansi ku muliro, okukuba ennimi z’omuliro n’okwokya omuliro ebweru mu diguli zonna 360 omulundi gumu.

Mu kiseera kye kimu, amazzi agakulukuta amangi agakulukuta agakwatagana n’okusala kw’ettaka n’okugatta ebifo by’omuliro bisobola okuwuuta waggulu ebiwujjo by’omuliro eby’amaanyi n’amaanyi g’omuyaga ebiwujjo ebiyitibwa pyrogenic vortices (firenadoes) nga ebbugumu ery’omunda ery’omusingi lisukka 1,090 degrees Celsius (2,000 degrees Fahrenheit) n’empewo ezitambula waggulu Kiromita 200 buli ssaawa (125 mph). Ensigo zino zisimbula emiti emikulu, zikyusa mmotoka, ziyuza obusolya ku bizimbe, ne zisuula ebifunfugu ebikutte omuliro okutuuka ku kiromita 5 (mayiro 3) mu maaso ga layini y’omuliro enkulu. Okumanya engeri y’okulaba obubonero obulabula obulabula obw’okugwa kw’ekiwujjo ekigenda okugwa oba okuwuuma kw’omuliro, lwaki olina okusenguka ng’omuliro gw’omu nsiko tegunnakyuka okuva ku kuvugibwa empewo okudda ku kufugibwa empewo, n’engeri y’okuwona ebbugumu eritangalijja munda mu mmotoka oba Ekifo eky’Obuddukiro eky’Ekiseera singa okukulukuta kutaasa obulamu.

Kino kikole kati¶

1. Senguka mangu ng’empagi y’omukka gw’omuliro gw’omu nsiko esimbiddwa mu vertikal ng’ekikondo ky’okubwatuka kw’okubwatuka oba okufuuka enzirugavu eya kakobe-enzirugavu. Tolinda kukonkona kutongole kusengulwa ku nnyumba ku mulyango singa olaba ekire kya kalittunsi ekinene ennyo ekyeru n’amanda (pyrocululus oba pyrocumulonimbus) ekizimbibwa butereevu waggulu w’omuliro ogw’omu nsiko oguli okumpi. Singa empagi eyo eyeesimbye egwa, omuliro gujja kugaziwa ebweru mu buli ludda lwa kkampasi ku sipiidi esinga ku sipiidi y’ebidduka y’amayumba gy’esobola okugogola ekitundu; okulaba omuliro ogw’omu nsiko.
2. Togezaako kudduka kudduka kiwujjo kya muliro oba ekifuluma mu kiwonvu (plume-collapse outflow) ng’otambula n’ebigere oba okulinnya olusozi oluwanvu. Ensigo z’omuliro zitambula mu ngeri etategeerekeka okuyita mu layini z’empewo ku sipiidi ya kiromita 30 ku 60 buli ssaawa (20 ku 37 mph), era ennimi z’omuliro ezidduka okulinnya ku diguli 30 oba ekiyumba ekifunda eky’omu kiwonvu zitambula emirundi ena ku munaana okusinga ku ttaka eritereevu. Tambula mu bbali okuva wansi w’ebiwonvu era ove ku amatandiiko aga topological amangu ago.
3. Bw’oba ​​osibye ku luguudo omuyaga gw’omuliro oba omuliro ogukubwa, sigala munda mu mmotoka yo eriko akasolya k’ekyuma. Emmotoka enzigale ekuwa obukuumi obulungi ennyo okuva ku bbugumu erya diguli 1,000 (diguli 1,830) n’omukka ogw’obutwa ogubuguma ennyo okusinga okudduka n’ebigere mu lujjudde. Paaka ku ttaka eryereere, amayinja oba kolaasi omugazi nga bwe kisoboka okuva ku bbulawuzi y’ekibira n’ebikomera eby’embaawo nga bwe kisoboka.
4. Tegeka mmotoka yo ekwatiddwa okusobola okwokya amangu ago. Yiringisiza amadirisa gonna waggulu ddala, ssaako amataala go n’ebitangaaza eby’akabi eby’amakubo ana abadduukirize basobole okukulaba ng’oyita mu mukka omuddugavu, yingini gireke nga tekola ng’empewo efuuwa esigaddewo yokka (giggale singa omukka gujjuza ekifo ekiyingira), kyusa ekyuma ekifuga embeera y’obudde ku Recirculate, era osse wansi ku ddaala ly’eddirisa erya wansi ku ddaala ly’endabirwamu ebikkiddwa mu bulangiti ey’ebyoya by’endiga oba ekkooti ya ppamba enzito.
5. Bw’okwatibwa munda mu kizimbe ng’omu maaso g’omuliro oba ekiwujjo ky’omuliro kikubye, weekuume munda mu kisenge eky’omunda okuva ku madirisa ag’ebweru era olondoole ku mwaliiro ogw’okungulu. Toddukirangako mu kkubo ng’omu maaso omukulu oguyaka omuliro guyita ebweru; ebbugumu eritangalijja lijja kwokya amawuggwe go n’okukuma omuliro mu ngoye mu sikonda ntono. Ggala enzigi zonna ez’omunda, ssika wansi kateni enzito oba bbulooka okuziyiza ebbugumu erimasamasa okuyita mu ndabirwamu, era obeere munda okutuusa ng’ennimi z’omuliro mu maaso ez’eddakiika 5 ku 15 ziyise, olwo ofulume amangu ddala ku ttaka eriddugavu eryayokebwa edda singa ennyumba ekwata omuliro.
6. Kuba ennamba yo ey’amangu mu kitundu kyo mu bwangu bw’oba osibye oba ng’osula mu kifo. Kuba 911 mu Amerika ne Canada, 112 okwetoloola omukago gwa Bulaaya, 000 mu Australia, oba 999 mu Bungereza (laba ennamba z’amangu) era oloope coordinates zo entuufu eza GPS oba endagiriro y’oku luguudo, omuwendo gw’abantu b’olina, n’okumanya oba weekukumye mu nnyumba, clearing, oba mmotoka.

Okutegeera ebikolwa by’omuliro ogw’amaanyi ogw’omu nsiko: okuwuuma kw’omuliro, okuwuuma kw’omuliro, n’okugwa kwa pyroCb¶

Bannasayansi b’omuliro mu nsiko n’abakugu mu by’obudde mu ggwanga baawula wakati w’omuliro ogwa bulijjo ogw’okungulu oguvugibwa empewo n’enkola ssatu ez’omuliro ez’omu bbanga ezisukkiridde ezimenya ebiseera ebya bulijjo eby’okuzikiza omuliro n’okusengula abantu.

flowchart TD
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    B -->|"Omukka gufukamira mu bbanga ku buwanvu obutono ng’empewo etakyukakyuka"| C["Omuliro oguvugirwa empewo: Ekkubo eriteeberezebwa okusaasaana; okuteekateeka Go-Bag n’okusenguka mu kkubo erisala empewo"]
    B -->|"Waggulu wa kalittunsi omweru eyeesimbye waggulu waggulu w’empagi enzirugavu, okumyansa okukalu, oba okukkakkana okw’amangu"| D["OKULABULA EKIKOLA KU PLUME / PYROCUMULONIMBUS (PyroCb) OKULABULA"]
    D --> E{"Ekire ekyesimbye waggulu kitandise okufuumuuka oba virga/evvu okutonnya wansi?"}
    E -->|"Nedda: Okukyasituka"| F["Senguka KATI: Okugwa kwa plume kuyinza okubaawo mu ddakiika 15 ku 30"]
    E -->|"Yee: Okuwuuma okw’amangu ku sipiidi ya kiromita 100 buli ssaawa (60 mph) okubwatuka okw’ebbugumu okw’enfuufu"| G["PLUME COLLAPSE ACTIVE: Omuliro gusaasaana diguli 360 + mass ember spotting 3 ku 5 km mu maaso"]
    G --> H{"Osobola okuvuga n’ofuluma ku luguudo olugazi olutangaavu?"}
    H -->|"Yee"| I["Vuga ng’ofuluma ng’amataala gaaka, amadirisa nga gaaka, A/C ng’eyaka Recirculate"]
    H -->|"Nedda: Oluguudo oluzibiddwa ennimi z’omuliro, waya ezigudde oba nga tezirabika"| J["Execute Burnover Survival Protocol: Ekizimbe ekinene munda OBA ekidduka ku ttaka obwereere"]

1. Ebiwujjo by’omuliro okusinziira ku kibuyaga z’omuliro entuufu (pyrogenic tornadic vortices) .¶

Wadde ng’abantu batera okuyita empagi yonna ey’ennimi z’omuliro ewuuta “firenado,” abakugu mu bya fiziiki mu muliro bagabanya ebiwujjo by’omuliro ebikyukakyuka mu mitendera ebiri egy’enjawulo okusinziira ku nsibuko yaabyo, obunene bwabyo, n’amaanyi ag’okuzikiriza:

Munda mu kiwujjo ky’omuliro, empalirizo ya centrifugal esuula empewo enzito ebweru ng’esonseka ggaasi eziwunya ezitayokeddwa (carbon monoxide, methane, ne vaporized wood tars) mu makkati ga puleesa entono mu vortex. Olw’okuba okisigyeni asobola okutabula ku nsalo ey’ebweru etabuddwatabuddwa ey’omusingi oguwuuta, ekiwujjo kino kiwanvuwa waggulu ne kifuuka ekiyumba ekiwanvu, ekikuŋŋaanyiziddwa eky’ennimi z’omuliro eziwuuta nga eyokya emirundi esatu ku etaano era nga ya mangu okusinga omuliro ogw’enkambi oguggule ogw’obunene bw’amafuta bwe bumu.

2. Enkuba y’omuliro eya Pyrocumulus (flammagenitus) ne pyrocumulonimbus (pyroCb).¶

Omuliro ogw’omu nsiko bwe gwokya nnyo nga guyita mu kibira ekinene, chaparral enkalu, oba ebizimbe by’omu bibuga, gukola ng’ekikoomi ekinene ennyo eky’amakolero, nga gupampagira gigawatts ez’amaanyi ag’ebbugumu n’obunnyogovu (okuva mu mubisi n’okwokya ebifuumuuka) butereevu waggulu mu bbanga:

1. Eddaala lya pyrocumulus: Nga omukka ogubuguma ennyo gulinnya emita enkumi n’enkumi, empewo egaziwa n’etonnya mu ngeri ya adiabatically okutuusa obunnyogovu lwe bufuuka ekire kya cumulus ekimasamasa, ekyeru ekimasamasa, ekifuukuuse nga kitudde ng’enkoofiira ya kalittunsi butereevu waggulu ku mpagi y’omukka enzirugavu enzirugavu.
2. Eddaala lya pyrocumulonimbus (pyroCb): Singa ebbugumu erifuluma mu muliro lisigala nga lya maanyi ate ng’embeera z’empewo ez’omutendera ogwa waggulu tezinywevu, empewo egenda waggulu egenda ku sipiidi esukka 100 ku 160 km/h (60 ku 100 mph) mu vertikal, ng’ekuba ddala okuyita mu ddaala ly’okutonnya n’etuuka ku tropopause oba stratosphere eya wansi ku 10 to Kiromita 16 (fuuti 33,000 okutuuka ku 52,000). Ebiwujjo bya ice n’omuzira bitondebwa munda mu mutwe gw’okubwatuka oguziyiziddwa omukka, ne bivaamu pyro-lightning ey’amaanyi (okusinga amaanyi ag’akabi aga positive-charge cloud-to-ground lightning bolts ezikuba ekibira ekikalu okutuuka ku kiromita 30 / mayiro 19 okuva ku muliro omukulu, ne zikuma omuliro omupya ogw’omu nsiko amakumi emabega w’abasenguddwa).

3. Fizikisi etta ey’okugwa kw’ekiwujjo kya pyroCb (okubumbulukuka) .¶

Ekiseera ekimu ekisinga okuba eky’obulabe mu muliro gwonna ogw’omu nsiko kibaawo ng’empagi empanvu eya pyrocumulonimbus egudde:

• Lwaki empagi egwa: Nga omuliro gwokya okuyita mu nsawo y’amafuta ennene oba okusisinkana okusala kw’empewo ey’obugulumivu, oba ng’enkuba n’omuzira ebigwa munda mu kire ekya waggulu bifuumuuka ne bifuuka empewo enkalu ey’omutendera ogw’omu makkati (okunyogoza ekibinja ky’empewo amangu ne kifuula ekinene era ekizito), okubuuka kw’ebbugumu okugenda waggulu kulemererwa mangu.
• The 360-degree downburst impact: Obukadde bwa ttani z’empewo ennyogovu, ezirimu evvu n’omukka bikka butereevu wansi okuva ku buwanvu bwa kiromita 8 (fuuti 26,000) ku sipiidi esukka mu kiromita 100 buli ssaawa (62 mph) ne bikuba wansi waggulu ddala ku muliro gw’omu nsiko ogukola. Okufaananako amazzi agayiibwa okuva mu baketi ku mmeeza, microburst downdraft eno ekuba ensi n’ebwatuka ebweru mu ngeri ey’amaanyi mu diguli zonna 360 omulundi gumu.
• Ebivaamu ku ttaka: Mu sikonda 120, empewo z’okungulu ezaali zifuuwa obutasalako ku sipiidi ya kiromita 25 buli ssaawa okuva mu maserengeta, zidda emabega mangu oba okubwatuka okutuuka ku sipiidi ya kiromita 100 ku 140 buli ssaawa (62 ku 87 mph) mu buli ludda. Omukka ogukka wansi gufuuwa ennimi z’omuliro empanvu mu ngeri ey’okwesimbye ku ttaka, ne gusooka okubugumya emiti egitayokeddwa, era ne gukuba omuyaga ogw’okwebungulula ogw’obukadde n’obukadde bw’ebiwujjo ebiyaka (firebrands) kiromita 3 ku 8 (mayiro 2 ku 5) mu maaso ga layini y’omuliro, ne gukuma omuliro mu bitundu byonna ng’omu maaso g’ennimi z’omuliro omukulu tegunnatuuka wadde.

Obubonero obulabula obulaba n’obusimu obw’okubwatuka oba okugwa kw’ekiwujjo ekigenda okubaawo¶

Teweetaaga bikozesebwa bya rada okukimanya nti omuliro ogw’omu nsiko oguli okumpi gukyuka ne gufuuka ogw’amaanyi ennyo, oguyinza okutta omuntu. Laba era owulirize ebipimo bino omukaaga eby’omu nnimiro ebyassibwawo ebitongole by’eggwanga ebizikiriza omuliro mu nsiko:

1. The smoke column shifts from bent-over gray to a vertical white-capped tower: A moderate smoke plume bends horizontally with the prevailing wind. If the smoke column stands straight up like a massive pillar and builds a bright white, boiling, cauliflower cloud cap (or flattens out at the very top into an icy thunderstorm anvil), the fire is now generating its own weather.
2. Empewo ey’amangu ey’obukkakkamu oba ey’okusika munda (indrafts): Nga tebannaba kufuumuuka nnyo oba okuwuuma kw’omuliro okuwuguka, omukka omunene ogw’ebbugumu ogw’omuliro gusonseka empewo eyeetoolodde munda ng’eyolekera omusingi gw’ennimi z’omuliro okuva kiromita. Singa empewo eyeetoolodde amaka go efa mangu okutuuka mu bukkakkamu obufu oba n’ekyusa obulagirizi olwo empewo n’efuuwa mu bbugwe w’omuliro agenda okusemberera, okugwa kw’omuliro okunene oba okugwa kw’amazzi (plume collapse) kuli kumpi.
3. Eggulu eriddugala olw’evvu erigwa, empiso za payini eyokeddwa, oba omuzira oguddugala: Singa ebikoola ebinene, ebitaliiko kamogo ebiyokeddwa, ebikoola bya payini, oba ebitundu by’evvu ebibuguma bitandika okutonnya ku kibanja kyo ng’okyali kiromita eziwerako okuva ku nnimi z’omuliro ezirabika, omukka ogw’amaanyi oguyitibwa convective updraft guba gusitula ebifunfugu mayiro waggulu ne bigusuula ku kasolya ko.
4. Streaks of dark virga (evaporating rain shafts) hanging underneath the smoke cloud: When dark, wispy curtains of rain fall out of the base of a pyroCb cloud and evaporate in the dry air before reaching the ground, that evaporative cooling accelerates a catastrophic downward microburst wind collapse.
5. A deafening freight-train roar: Both large fire whirls and crown-fire blowups produce an unmistakable, deep acoustic roar caused by millions of cubic meters of air being sucked into the combustion zone and spinning at tornadic velocities.
6. Barometric pressure drops and dry lightning flashes inside the smoke: Frequent jagged lightning bolts jumping out of the dark smoke column without wetting rain signal an active pyrocumulonimbus storm.

Terrain traps that multiply fire speed and trigger fire whirls¶

Topography dictates where fire whirls form and where flames accelerate beyond human survival thresholds. Never use these four terrain features as an evacuation path or refuge during an active wildfire:

How to evacuate before a plume-dominated fire traps your neighborhood¶

During extreme wildfire events, the majority of civilian fatalities occur during late evacuations on narrow, smoke-blinded roads clogged with stalled cars, fallen utility poles, and downed trees.

1. Leave at the "Ready / Set" (Advisory) stage, never wait for "Go" (Mandatory) if extreme fire weather is forecast: When national weather agencies issue a Red Flag Warning or Extreme Fire Danger alert (characterized by relative humidity below 15 percent, temperatures above 32°C / 90°F, and winds above 40 km/h / 25 mph), prepare your vehicle immediately. Back your car into the garage or driveway facing the street with the windows rolled up and your go-bag evacuation pack loaded inside.
2. Identify at least two orthogonal evacuation routes: Because a pyroCb plume collapse blasts fire outward in all directions and fire whirls jump highways, your primary road may be cut off in minutes. Map a primary route and a secondary route that travels at a 90-degree angle to the wind toward wide agricultural fields, large paved parking lots, beaches, or urban centers.
3. Dress every family member in 100 percent natural-fiber long clothing before walking out the door: Put on heavy 100 percent cotton denim jeans, a long-sleeved cotton or wool shirt, sturdy leather boots, leather work gloves, a cotton bandana or N95/P100 respirator, and wrap-around goggles (see wildfire smoke and ash inhalation). Never wear polyester, nylon, fleece, or spandex athletic wear during a wildfire evacuation: synthetic fabrics melt into burning liquid plastic against your skin when exposed to radiant heat or flying embers long before cotton ignites.
4. Disconnect your automatic garage door opener before the power grid fails: High winds and fire whirls snap power lines early in a wildfire. Pull the red manual emergency release cord on your overhead garage door track now so you are never trapped inside a dark garage with your car when the electricity cuts out.

Last-resort burnover survival: what to do if you are trapped and overrun¶

If your evacuation route is completely blocked by a wall of flame, fallen power lines, or zero-visibility black smoke during a plume collapse, you must immediately transition from driving to burnover survival. The critical fact to remember is that the deadly flaming front of a wildfire typically takes only 5 to 15 minutes to pass over a fixed point. If you can shield your body and airway from radiant heat and superheated gases during those 10 minutes of peak flame passage, you can survive and step out onto the cooled, already-burned black ground afterward.

Hierarchy of last-resort wildfire refuges (from safest to most dangerous)¶

Option 1: Inside a substantial, well-prepared building (Safest refuge)¶

Wildland survival data from Australia, the United States, and Southern Europe consistently proves that sheltering inside a solid building offers a vastly higher survival rate than fleeing on foot or driving blindly into dense smoke at the last minute:

• Bring everyone inside and close every exterior door, window, and vent: Shutting windows blocks 70 to 90 percent of exterior radiant heat and stops the indoor wind tunnel of flying embers.
• Turn OFF the main household natural gas valve and outdoor propane tank valve: If your house catches fire after the front passes, closed gas valves prevent secondary gas explosions.
• Leave interior lights ON and fill sinks, bathtubs, and buckets with water: When thick black pyroCb smoke turns midday into pitch-black midnight and the power grid fails, water reserves help extinguish small ember spots around window sills.
• Close curtains or metal blinds, move upholstered furniture away from windows, and shelter in a room on the side farthest from the approaching fire that has a direct exterior door to clear/burned ground.
• Watch the ceiling and attic manhole continuously: Houses rarely ignite from a wall of flame hitting the outside siding; instead, tiny wind-blown embers suck through roof eaves and attic vents during an ember storm, igniting the attic from the inside. Keep a ladder under the attic hatch and check it every few minutes.
• When to exit the house: Stay inside while the roaring flame front passes outside (usually 5 to 15 minutes). If the roof or walls of your house catch fire and fill the rooms with black toxic smoke, wait until the exterior hurricane of flame has subsided, cover your body completely in dry wool blankets (never soaking wet blankets, which conduct steam heat into your skin under intense radiant flux), hold a damp cloth over your nose and mouth, and walk out the leeward door directly onto already-burned black ground ("the black") or a wide paved driveway.

Option 2: Inside a stationary closed vehicle on bare ground (Second-best refuge)¶

If you are caught on a highway or rural road and cannot reach a solid building:

1. Do NOT abandon your car to run down the road on foot: People who panic and jump out of stalled cars to run through a wildfire are almost always overcome by radiant heat (which reaches 20 to 40 kilowatts per square meter), zero visibility, and 300-degree-Celsius (570-degree-Fahrenheit) air within 50 meters (165 feet).
2. Park on the widest, barest patch of ground available: Pull onto a gravel turnout, dirt intersection, wide asphalt shoulder, or rock cut, or park behind a solid concrete bridge abutment or earthen bank that blocks the direct line of sight to the tallest trees. Avoid parking directly over dry tall grass or right against heavy roadside brush.
3. Angle the rear or side of the vehicle toward the approaching fire if time permits, turn on hazard flashers and headlights, and shut all windows and sunroofs tightly.
4. Set air conditioning vents to Recirculate (closed outside air damper), then shut off the engine once smoke thickens.
5. Get down on the floorboard below the window glass line: Tempered side windows can shatter if hit by flying fire-whirl debris or extreme uneven thermal stress. Crouch or lie flat on the floor wells beneath the level of the steel doors (which block 100 percent of infrared radiant heat) and pull a wool blanket, heavy cotton jacket, or even the car's cloth floor mats completely over your head, neck, and hands.
6. Expect terrifying noise, heat, and rocking: As the flame front passes over the car for 3 to 8 minutes, howling outflow winds will rock the suspension, smoke may seep around door gaskets, the tires may pop or catch fire, and exterior plastic trim may melt. Stay down under your wool blanket until the peak roar and orange glare subside. Modern fuel tanks rarely explode during the initial pass; only exit the vehicle onto the burned black ground once the external flame wall has moved past or if active fire penetrates the passenger cabin itself.

Option 3: Open-ground Temporary Refuge Area (Last resort if caught on foot outdoors)¶

If you are hiking or working outdoors without a vehicle or building when a fire whirl or blowup traps you:

• Head immediately for "the black" (already burned ground) if accessible: Ground that has already burned clean of fuel cannot burn a second time; it is the safest place in the area once cooled slightly.
• If you cannot reach the black, find the largest bare clearing, rock scree field, dirt road, gravel riverbed, or plowed field available.
• Alternatively, submerge in a deep pond, lake, river, or cold swimming pool: Beware of shallow plastic above-ground pools (which melt and collapse) or shallow creeks surrounded by overhanging forest canopy (where superheated air and carbon monoxide still blanket the water surface). Keep your clothing on and breathe right at the cool water surface through a wet cotton cloth.
• If forced to survive on bare dirt with no water: Scrape away all dry leaves and twigs down to bare mineral soil in a circle as wide as possible. Dig a shallow trench in the dirt, lie flat face-down with your feet pointed toward the approaching flames, press your face into a hollow in the cool soil breathing through a moistened cotton cloth (never breathe upward into the superheated air layer), and cover every millimeter of exposed skin with dirt, wool, or cotton layers until the flame front passes over you.

Ebibuuzo ebitera okubuuzibwa¶

What is the difference between a fire whirl and a true fire tornado (firenado)?¶

A common fire whirl is a localized spinning column of flame and ash, usually 1 to 50 meters (3 to 165 feet) wide, formed near the ground when intense surface heat rises and stretches horizontal wind shear around ridges or merging fire lines. A true fire tornado (pyrogenic tornadic vortex) is a massive, meteorology-driven tornado directly connected to the rotating updraft of a towering pyrocumulonimbus thunderstorm cloud high above the fire; it can exceed 300 meters (1,000 feet) in width, generate EF-2 to EF-3 winds above 220 km/h (135 mph), burn at over 1,090 degrees Celsius (2,000 degrees Fahrenheit), and stay on the ground for over an hour.

Why is a pyrocumulonimbus (pyroCb) plume collapse so dangerous to people evacuating a wildfire?¶

While a pyrocumulonimbus smoke column is actively rising 10 to 15 kilometers (33,000 to 50,000 feet) into the sky, its powerful updraft sucks air inward toward the fire. When the upper cloud cools or hits wind shear and the updraft suddenly fails, millions of tons of dense air plunge straight down onto the fire in a violent microburst. Upon hitting the ground, this downdraft blasts outward in all 360 degrees at 90 to 140 km/h (55 to 85 mph), causing the wildfire to explode rapidly in every direction at once while showering burning embers up to 5 kilometers (3 miles) ahead of the main fire line.

If my car is trapped on a road by an advancing wildfire, should I get out and run on foot?¶

No, never abandon a closed metal vehicle to flee on foot during a wildfire burnover. Walking or running in the open exposes your bare skin and lungs directly to lethal radiant heat fluxes and superheated gases above 200 degrees Celsius (400 degrees Fahrenheit), which cause fatal airway burns and collapse within seconds. Instead, park your vehicle on the barest patch of pavement, gravel, or dirt away from heavy trees, roll up all windows, set air vents to Recirculate, turn on hazard lights, and crouch down on the floorboard below the window glass covered completely in a wool blanket or cotton clothing until the 5-to-15-minute flame front passes.

Why should I cover myself with a dry wool blanket instead of a soaking wet blanket during a wildfire burnover?¶

During the intense radiant and convective heat pulse of a wildfire burnover, water soaked into a blanket or clothing resting against your body can rapidly heat to 100 degrees Celsius (212 degrees Fahrenheit) and turn into scalding steam, conducting heat seven times faster into your skin than dry air and causing severe steam burns. Use a dry 100 percent wool blanket or heavy cotton coat as your outer thermal shield to block radiant heat, and use only a lightly dampened cotton cloth held over your nose and mouth to cool and filter the air you breathe.

Ensonda zeekebeddwa¶

• National Wildfire Coordinating Group (NWCG) and United States Forest Service (USFS, United States): S-290 Intermediate Wildland Fire Behavior: Plume-Dominated Fires, Fire Whirls, and Entrapment Avoidance
• Country Fire Authority (CFA, Victoria) and NSW Rural Fire Service (Australia): Bushfire Survival Guide: Radiant Heat Protection, Sheltering in a Building, and Vehicle Burnover Procedures
• National Weather Service (NWS) and NOAA (United States): Pyrocumulus, Pyrocumulonimbus (PyroCb) Downdrafts, and Fire Tornado Case Studies
• Federal Emergency Management Agency (FEMA / Ready.gov, United States) and CAL FIRE: Wildfire Evacuation: Ready, Set, Go and Ember Storm Preparedness
• Canadian Interagency Forest Fire Centre (CIFFC) and Natural Resources Canada: Extreme Wildfire Behavior and Pyrogenic Vortex Dynamics

Ebiragiro ebikwatagana nabyo¶

• Wildfires: evacuation, defensible space, and survival
• Omukka gw’omuliro gw’omu nsiko n’okussa evvu
• Post-wildfire burn scar mudslides and debris flow evacuation
• Okwokya n’okwokya obujjanjabi obusookerwako
• Go-bag okusengula abantu