Yanayin Dallas

Dallas tana cikin Arewacin Texas, an gina ta a gefen Kogin Triniti . Yana da yanayin zafi mai zafi (Köppen climate classification: Cfa) wanda ke da halaye na filayen kudancin Amurka. Dallas tana fuskantar hunturu mai sauƙi da lokacin zafi.

## Yanayin yanayi

### Lokacin bazara
Lokacin zafi yana da zafi sosai kuma yana da ɗanɗano. Zafi na iya zama mai tsanani da tsawaitawa, yawanci ya zo daidai da fari mai tsanani. Matsakaicin yawan zafin jiki na birni da aka rubuta shine 113 °F (45 °C) a lokacin Zafi na 1980. A cikin Yuli da Agusta, matsakaicin matsakaicin zafin jiki yana kusa da 96 °F (36 °C), yayin da matsakaicin lokacin zafi ya kai 7°F.  Kwanaki tare da yanayin zafi sama da 100 °F (38 °C) na faruwa aƙalla sau da yawa a lokacin bazara kowace shekara.  Musamman lokacin zafi da bushewa ya faru a cikin 1980, 2011, 2022 da 2023.

### Watanni na canji
Lokacin bazara da kaka suna kawo yanayin zafi a yankin. Fure-fure na daji (kamar bluebonnet, Indian paintbrush da sauran tsire-tsire) suna fure a cikin bazara kuma ana dasa su a kusa da manyan hanyoyi a duk fadin Texas. Yanayin bazara na iya zama mai saurin canzawa, amma yanayin zafi da kansa yana da dumi a matsakaici. Yanayi a Dallas kuma yana da kyau tsakanin ƙarshen Oktoba da farkon Disamba, kuma ba kamar lokacin bazara ba, manyan guguwa ba sa samuwa a yankin.

A cikin bazara, ginshiƙai masu sanyi da ke motsawa kudu daga Kanada sun hail da iska mai dumi, mai laushi daga Gulf Coast. Lokacin da waɗannan gaba suka haɗu a arewacin tsakiyar Texas, ana haifar da tsawa mai tsanani tare da nuna walƙiya mai ban mamaki, ruwan sama, ƙanƙara, kuma a wasu lokuta, guguwa (Dallas yana cikin ƙananan ƙarshen Tornado Alley).

### Lokacin hunturu
A cikin watannin hunturu na Disamba zuwa Maris, yawan zafin rana da ya kai 76.7-85.9°F (24.8–29.9°C) ba sabon abu bane a lokacin zafi mai zafi.  A gefe guda kuma, Blue Norther na iya faruwa, yana kawo faɗuwar zafin jiki kwatsam kuma mai yuwuwa.  A lokacin sanyi, yanayin zafi mai girma na iya raguwa zuwa 30s F., tare da ƙananan yanayin zafi a cikin kewayon 10-20 F., da wuya ƙasa da wancan, na kwanaki da yawa.  Sau biyu a kowace shekara, iska mai dumi da danshi daga kudu takan kawar da sanyi, busasshiyar iska, wanda ke haifar da daskarewar ruwan sama, wanda yakan haifar da babbar matsala a cikin birni idan tituna da manyan tituna suka yi tauri.  A matsakaita, ko da mafi sanyin watan Janairu gabaɗaya mai laushi ne, tare da matsakaicin tsayi na 57.7 °F (14.3 °C) da ƙasan 37.9 °F (3.3 °C).  Dangane da bayanan yanayi na 1991-2020, matsakaicin zafin jiki mafi sanyi na tsawon shekara guda shine kusan 19.1 °F (-7.2 °C), sanya Dallas a yankin USDA 8b.  Mafi ƙarancin lokaci da aka yi rikodin shine -3 °F (-19 °C) ranar 18 ga Janairu, 1930.

## Snow
Akwai kwana biyu zuwa uku tare da ƙanƙara a kowace shekara, amma dusar ƙanƙarar ba ta da yawa. Dangane da rubuce-rubuce daga 1898 zuwa 2019, matsakaicin dusar ƙanƙara shine inci 2.6 a kowace shekara. Ya yi dusar ƙanƙara sau biyu a lokacin wasannin kwallon kafa na NFL a Filin wasa na Texas, a cikin 1993 da 2007, wanda ya kasance da wuri. Watan da ke da mafi girman dusar ƙanƙara yawanci Fabrairu ne, tare da matsakaicin inci 0.6 da ke fadowa. Duk da yake watan da ke da mafi yawan kwanaki tare da dusar ƙanƙara yawanci Janairu ne, tare da matsakaicin kwanaki 0.5 na dusar ƙara. An yi rikodin dusar ƙanƙara a watan Fabrairun 2010, lokacin da inci 12.5 na dusar ƙara ya faɗi sama da kwana biyu a filin jirgin saman Dallas-Fort Worth.

## Yanayi mai saurin tashi

### Guguwa

Tun lokacin da Dallas ke ƙasa a ƙarshen "Tornado Alley", guguwa a wasu lokuta sun kasance barazana ga birnin. Yawancin guguwa sun mamaye birnin a cikin watanni na Afrilu da Mayu. guguwa mai karfi ta buge Dallas a ranar 2 ga Afrilu, 1957; daga baya aka sanya guguwar F3. A ranar 28 ga Maris, 2000, "Fort Worth Tornado">Fort Worth Tornado" ya shafi maƙwabcin Dallas na Fort Worth, kuma guguwa a Arlington, Texas ma ta faru a wannan rana ta lalata wasu gidaje. Mutane hudu sun mutu a Fort Worth sakamakon guguwar. Wannan rana ita ce mummunar fashewar guguwa ta Metroplex tun bayan taron 1957. Wani yaduwar guguwa ya mamaye yankin a cikin yaduwar Dallas a ranar 3 ga Afrilu, 2012, ya ɗan lalata Rangers Ballpark a Arlington kuma ya lalata wasu jiragen sama kuma ya rushe wasu a Filin jirgin saman Dallas / Fort Worth da Dallas Love Field, ya lalata makarantar firamare sosai, kuma ya lalata semis a cikin kayan aiki. A ranar 26 ga watan Disamba, 2015, wani yaduwar guguwa ta hunturu ya haifar da yaduwar hadari da yawa, gami da Guguwar EF4 kusa da garin Garland da Rowlett wanda ya haifar da mutuwar 10. A ranar 21 ga Oktoba, 2019, guguwa 10 sun sauka a cikin Dallas-Fort Worth Metroplex, gami da guguwar EF3 da ta lalata yankuna daga Arewacin Dallas zuwa Richardson . 

### Ambaliyar ruwa
Babban ambaliyar ruwa ta faru a kan Kogin Triniti a cikin shekarun 1844, 1866, 1871, da 1890, amma babban abin da ya faru a cikin bazara na 1908 ya fara amfani da kogin. A ranar 26 ga Mayu 1908, Kogin Triniti ya kai zurfin ƙafa 52.6 (16.03  da faɗin mil 1.5 (2.4 .  Mutane biyar sun mutu, 4,000 sun rasa gida, kuma an kiyasta lalacewar dukiya a dala miliyan 2.5.

Dallas ba ta da wutar lantarki har kwana uku, duk sabis na tarho da telegraph sun ragu, kuma an soke sabis na jirgin ƙasa. Hanyar da za a isa Oak Cliff ita ce ta jirgin ruwa. Yammacin Dallas ya fi kowane bangare na birnin rauni - *Dallas Times Herald* ya ce "ba za a iya bayyanawa ba" ya addabi yankin. Abin tsoro ga mazauna, dubban dabbobi sun nitse a cikin ambaliyar kuma wasu sun zauna a saman bishiyoyi - ƙanshin lalacewarsu ya rataye a kan birni yayin da ruwa ya ragu.

Bayan ambaliyar ruwa mai bala'i, birnin ya so ya sami hanyar sarrafa Triniti mara hankali da  gina gada da ke haɗa Oak Cliff da Dallas. Halin nan da nan ya kasance 'yan ƙasa da birni suna ihu don gina hanyar da ba za a iya rushewa ba, duk yanayin da ke ƙetare Triniti. An riga an gwada wannan bayan ambaliyar 1890 - sakamakon shine "Long Wooden Bridge" wanda ya haɗa Jefferson Boulevard a Oak Cliff da Cadiz a Dallas, amma ambaliyar 1908 ta wanke gadar da ba ta da kwanciyar hankali. George B. Dealey, mai wallafa Dallas Morning News, ya ba da shawarar gadar kankare mai nisan kilomita 2.4 wanda ya dogara da gadar da ke tsallaka Kogin Missouri a Kansas City. Daga ƙarshe an amince da zaben takardar shaidar US $ 650,000 kuma a cikin 1912, an buɗe hanyar Oak Cliff (yanzu Houston Street Viaduct) tsakanin bukukuwan da suka jawo masu kallo 58,000 . Ginin, a lokacin, shine tsarin kankare mafi tsawo a duniya.

A watan Mayu na shekara ta 2015, Filin jirgin saman Dallas-Fort Worth ya sami ruwan sama mai yawa a cikin wata daya da ya shafe rikodin ruwan sama mai tsanani kusan a ko'ina cikin Kudancin Filayen (Texas da Oklahoma, musamman).  Abin mamaki, lokacin rani mai zafi, ya biyo baya, wanda ya haifar da wasu sassan Texas da suka koma yanayin bushewa a farkon watan Yulin 2015, jim kadan bayan rikodin ruwan sama na Mayu ya share yanayin fari na shekaru a yankin.

## El Niño-Kudancin Oscillation
El Niño-Southern Oscillation (ENSO) yana ƙayyade mafi yawan abin da watanni na hunturu da bazara suke kamar a Dallas.  A lokacin zafi (El Niño), hunturu da bazara sun fi sanyi kuma suna samun dusar ƙanƙara fiye da yadda aka saba.  A ƙarƙashin yanayin sanyi (La Niña), hunturu da bazara sun fi zafi kuma suna samun ƙarancin dusar ƙanƙara.

## Bayani